FLIGHT SAFETY FOUNDATION

JULY–AUGUST 1996 FLIGHT SAFETY DIGEST

SPECIAL DOUBLE ISSUE -bound Flight Crew’s Improperly Flown Nonprecision Instrument Approach Results in Controlled-flight-into-terrain Accident

Report Special CFIT Safety FLIGHT SAFETY FOUNDATION For Everyone Concerned Flight Safety Digest With the Safety of Flight Vol. 15 No. 7/8 July–August 1996 Officers/Staff In This Issue Stuart Matthews Dubrovnik-bound Flight Crew’s Chairman, President and CEO Improperly Flown Nonprecision 1 Board of Governors Instrument Approach Results in James S. Waugh Treasurer Controlled-flight-into-terrain Accident Robert Reed Gray, Esq. An analysis of the terrain profile, accident General Counsel and Secretary configuration and flight profile Board of Governors determined that the accident aircraft’s ground- proximity warning system would not have ADMINISTRATIVE provided a warning to the crew, the official U.S. Nancy Richards Air Force report said. Executive Secretary FINANCIAL FSF CFIT Checklist 26 Brigette Adkins Accountant Worldwide Commercial Jet Transport 30 TECHNICAL Accident Rates Declined in 1995 Robert H. Vandel There were nine fatal accidents in 1995 Director of Technical Projects compared with 14 in 1994, and the fatal-accident Ellen Plaugher rate was lower than in all but two years since Secretary 1960.

MEMBERSHIP FAA Advisory Circular Outlines Ahlam Wahdan New Method for Designing Airport 34 Assistant to the Director of Membership and Development Pavement for Book offers a new look at procedures for PUBLICATIONS avoiding midair collisions. Roger Rozelle Director of Publications MD-87 Crew Makes Mistaken Approach Girard Steichen To Military Airport 44 Assistant Director of Publications Rick Darby Sightseeing helicopter downed by fuel Senior Editor exhaustion at air show. C. Claire Smith Cover: Wreckage of aft fuselage and empennage at crash site of U.S. Air Editorial Consultant Force CT-43A (-200), Dubrovnik, , April 3, 1996. Photo: AP/Wide World Photos Karen K. Ehrlich Production Coordinator Flight Safety Foundation is an international membership organization Kathryn L. Ramage Librarian, dedicated to the continuous improvement of flight safety. Nonprofit Jerry Lederer Library and independent, FSF was launched in 1945 in response to the aviation industry’s need for a neutral clearinghouse to disseminate objective safety information, and for a credible and knowledgeable body that would identify threats to safety, analyze the problems and recommend Jerome Lederer practical solutions to them. Since its beginning, the Foundation has President/Emeritus acted in the public interest to produce positive influence on aviation safety. Today, the Foundation provides leadership to more than 660 member organizations in 77 countries. Foreword

In 1991, Flight Safety Foundation (FSF) launched an international campaign to reduce the number of controlled-flight-into- terrain (CFIT) accidents, which was expanded later to include approach-and-landing accidents. An FSF-led task force, in counsel with the International Air Transport Association (IATA) and the International Civil Aviation Organization (ICAO), was formed and set as its goal to reduce by 50 percent the number of CFIT accidents by 1998. The FSF CFIT Task Force, which in 1994 received an Aviation Week & Space Technology Aerospace Laurel award for its work, includes representatives from airlines, equipment manufacturers, airframe manufacturers, professional aviation organizations and other technical and research organizations (see page iii).

CFIT accidents are the leading cause of commercial aviation fatalities. According to FSF CFIT Task Force statistics, CFIT and approach-and-landing accidents accounted for more than 80 percent of the fatalities in commercial transport accidents between 1979 and 1991. According to statistics compiled by McDonnell Douglas (see page 30), there were four commercial jet transport CFIT accidents in 1995. Approach-and-landing accidents in 1995 continued to be prominent among commercial jet transport accidents, with 20 such accidents worldwide.

As part of the overall CFIT-reduction plan, the FSF CFIT Task Force has developed several products including:

• An “FSF CFIT Safety Alert” distributed to thousands of operators worldwide at no cost to recipients that emphasized the importance of immediate and aggressive “pull-up” actions, unless circumstances (visual meteorological conditions and flight well-above flat terrain, for example) explicitly determined that a ground-proximity warning system (GPWS) warning was false. Early FSF CFIT Task Force findings had determined that flight crews in CFIT accidents often ignored GPWS warnings; delayed recommended pull-up procedures while trying to evaluate the accuracy of the GPWS warning; or failed to respond with sufficient aggressive pull-up action.

• An “FSF CFIT Checklist,” which helps pilots assess CFIT risks for specific flights and operations. To date, more than 30,000 copies of the FSF CFIT Checklist (reproduced following page 25) have been distributed by the Foundation worldwide with the help of sponsorships from FlightSafety International, System (SAS) and SimuFlite Training International at no cost to the recipients. The English version remains available at no charge. Additional sponsorships are being sought to distribute Chinese, Russian, French, Spanish and Arabic versions of the CFIT Checklist, which were translated by ICAO.

• A video training aid, CFIT: Awareness and Prevention, which examines several CFIT accidents and presents cockpit voice recorder (CVR) data and simulation to illustrate accident reduction strategies. More than 6,000 copies of the video were distributed worldwide in 1995 (4,500 at no cost, with major funding from Associated Aviation Underwriters (AAU), Gulfstream Aerospace and Jeppesen Sanderson). Copies of CFIT: Awareness and Prevention are available from the Foundation for US$30; and,

• The CFIT Education and Training Aid, a two-volume training package developed under the auspices of the FSF CFIT Task Force and produced by the Boeing Commercial Airplane Group. Scheduled for release in late 1996, the training aid examines a number of CFIT accidents and focuses on human factors and management issues. The comprehensive training aid, which contains data to design simulator escape-maneuver training, is intended to be a resource for developing policies, procedures and CFIT-avoidance standards. The training aid also includes the video Controlled Flight into Terrain: An Encounter Avoided, which analyzes a jet transport CFIT accident in detail and shows how such accidents can be avoided. A price for the CFIT Education and Training Aid has not been determined, but it is designed to be an affordable training product for a wide range of aviation operators.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 i The FSF CFIT Task Force has also made eight recommendations to ICAO. A recommendation to broaden requirements for the use of GPWSs has been adopted by ICAO, and the others are under review. The new GPWS standards, effective Dec. 31, 1998, require GPWS in all aircraft used in “international commercial and general aviation operations, where the MCTM [maximum certified mass] is in excess of 5,700 kilograms [12,500 pounds] ... or that are authorized to carry more than nine passengers.”

ICAO officials have indicated their support for the pending recommendations, which include:

• A call for color-shaded depictions of terrain altitude on instrument-approach charts;

• A warning against the use of three-pointer and drum-pointer altimeters;

• A recommendation that all countries adopt the use of hectopascals for altimeter settings;

• A call for the replacement of early-model GPWS equipment;

• A recommendation for the improved design and presentation of nonprecision instrument approach procedures with a standard three-degree approach slope, except where prohibited by obstacles;

• A call for the use of automated altitude call-outs; and,

• A recognition of the important CFIT-avoidance benefits provided by the global positioning system/global navigation satellite system (GPS/GNSS).

CFIT accidents involving commercial operators were examined in detail in a special April–May 1996 double issue of the Flight Safety Digest. The research focused on 156 CFIT accidents that occurred from 1988 through 1994. The report, “An Analysis of Controlled-flight-into-terrain (CFIT) Accidents of Commercial Operators, 1988 through 1994,” concluded that 75 percent of the 108 accident aircraft (for which data were available) were not equipped with a GPWS and that landing (descent)-phase and landing (approach)-phase accidents together accounted for nearly 70 percent of all CFIT accidents studied. The report also noted that nearly 60 percent of landing (approach)-phase accidents involved aircraft flying nonprecision approaches. Twenty- five percent of the approaches were very high frequency omnidirectional radio range (VOR) DME approaches.

Another FSF report, prepared for the Directorate-General of Civil Aviation of the Netherlands and published in the March 1996 Flight Safety Digest, determined that there was a “five-fold increase in accident risk among commercial aircraft flying nonprecision approaches compared to those flying precision approaches.” The report, “Airport Safety: A Study of Accidents and Available Approach-and-landing Aids,” said that the “chance for error by the crew is probably greater during a nonprecision approach compared to a precision approach, resulting from the increased workload and additional need to maintain situational awareness.” According to FSF CFIT Task Force statistics for the period 1988 through 1995, 15 CFIT accidents involved distance-measuring equipment (DME) stepdown approaches. The FSF CFIT Task Force concluded that such nonprecision approaches are unnecessarily hazardous.

The Foundation’s CFIT accident–reduction campaign, like other FSF-led efforts in the areas of wind shear accident avoidance and fatigue countermeasures, was designed to bring the resources of the industry together to work toward the common goal of improving an already admirable safety record.

— Stuart Matthews Chairman, President and CEO Flight Safety Foundation

ii FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 FSF CFIT Task Force

Following is a list of companies whose representatives launched the initial FSF CFIT Task Force. Since its formation, many additional companies and individuals have participated in the task force’s work.

Aeroformation Flight Safety Foundation Aerospatiale Inc. (now Aero International Regional) Flight Safety Foundation-CIS Air Canada FlightSafety International Air Line Pilots Association (ALPA) Gulfstream Aerospace Corp. Air Traffic Control Association (ATCA) International Air Transport Association (IATA) Airbus Industrie International Civil Aviation Organization (ICAO) Airclaims Group Ltd. International Federation of Air Line Pilots All Nippon Airways (ANA) Co. Ltd. Associations (IFALPA) Allegheny Airlines Inc. International Federation of Air Traffic Controllers’ Association (IFATCA) AlliedSignal Aerospace Japan Airlines American Express Bank Ltd. Jeppesen Sanderson Inc. Atlantic Southeast Airlines (ASA) KLM—Royal Dutch Airlines Australian Airlines The Kroger Co. Avions de Transport Regional Lockheed Martin Corp. BA Acrad German Airlines Beechcraft Middle East Airlines The Boeing Co. Monsanto Co. Britannia Airways Ltd. U.S. National Aeronautics and Space Administration (NASA) — Ames Research Center Canada 3000 Airlines Inc. National Business Aircraft Association (NBAA) Cessna Aircraft Co. Netherlands National Aerospace Laboratory (NRL) Comair Inc. Pakistan International Airlines Corp. Continental Airlines Inc. Raytheon Co. de Havilland Inc. SimuFlite Training International Inc. Smiths Industries Aerospace Dresser Industries Sundstrand Corp. Douglas Aircraft Co. U.S. Federal Aviation Administration (FAA) S.A. Oy Vereiningung Cockpit E.V.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 iii Additional CFIT-related Reading from FSF Publications

“Helicopter Strikes Water on Approach After Pilots Lose Altitude Awareness,” Helicopter Safety Volume 22 (July-August 1996). “Different Altimeter Displays and Crew Fatigue Likely Contributed to Canadian Controlled-flight-into-terrain Accident,” Accident Prevention Volume 52 (December 1995). “Commuter Crew’s Loss of Situational Awareness During Night Takeoff Results in Controlled Flight into Terrain,” Accident Prevention Volume 52 (October 1995). “Crew’s Failure to Monitor Terrain Clearance After Night Takeoff Results in Collision with Mountain,” Accident Prevention Volume 52 (September 1995). “Poorly Flown Approach in Fog Results in Collision with Terrain Short of ,” Accident Prevention Volume 52 (August 1995). “Failure to Intercept Final Approach Course, Improperly Performed IFR Approach Cited in Fatal Collision with Terrain,” Helicopter Safety Volume 21 (May-June 1995). “Aircraft Descended Below Minimum Sector Altitude and Crew Failed to Respond to GPWS as Chartered Flew into Mountain in Azores,” Accident Prevention Volume 52 (February 1995). “Breakdown in Coordination by Commuter Crew During Unstabalized Approach Results in Controlled-flight- into-terrain Accident,” Accident Prevention Volume 51 (September 1994). “Lack of Management Oversight Cited in Controlled-flight-into-terrain Accident of FAA Aircraft,” Accident Prevention Volume 51 (August 1994). “Captain Stops First Officer’s Go-around, DC-9 Becomes Controlled-flight-into-terrain (CFIT) Accident,” Accident Prevention Volume 51 (February 1994). “Cockpit Coordination, Training Issues Pivotal in Fatal Approach-to-Landing Accident,” Accident Prevention Volume 51 (January 1994). “Fatal Commuter Crash Blamed on Visual Illusion, Lack of Cockpit Coordination,” Accident Prevention Volume 50 (November 1993). “Anatomy of a Mountain Crash: Error Chain Leads to Tragedy,” Accident Prevention Volume 49 (October 1992).

iv FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Dubrovnik-bound Flight Crew’s Improperly Flown Nonprecision Instrument Approach Results in Controlled-flight-into-terrain Accident

An analysis of the terrain profile, accident aircraft configuration and flight profile determined that the accident aircraft’s ground-proximity warning system would not have provided a warning to the crew, the official U.S. Air Force report said.

FSF Editorial Staff

On April 3, 1996, the crew of the U.S. Air Force CT-43A The accident flight crew and aircraft were assigned to the Air (Boeing 737-200) was flying a nondirectional radio beacon Force 76th Airlift Squadron (76 AS), 86th Operations Group (NDB) approach in instrument meteorological conditions (86 OG), 86th Airlift Wing (86 AW) at Ramstein Air Base (IMC) to Runway 12 at the Cilipi Airport, Dubrovnik, (AB), Germany. The crew’s mission was to transport U.S. Croatia, when the aircraft collided with a 701-meter (2,300- Department of Commerce Secretary Ronald H. Brown and a foot) mountain. All six crew members and all 29 passengers delegation of U.S. industry executives from , Croatia, were killed in the accident. to various locations in Bosnia-Herzegovina and Croatia during a three-day period. The accident occurred on the first day, on As the aircraft crossed the final approach fix (FAF), it had an the fourth leg of a five-leg trip. airspeed of approximately 209 knots (387 kilometers per hour), which was 30 knots (56 kilometers per hour) faster than the The itinerary was changed four times before the flight began. airspeed recommended in the airplane’s flight manual for The crew planned the mission on April 1 (two days before the crossing the FAF. accident flight), based on the information in Change 1 to their itinerary. A stop in Dubrovnik was not listed in the change. As they flew the approach, the crew did not track the final- approach course of 119 degrees, but instead tracked a course The pilot of the flight “was known for very thorough mission of 110 degrees. They maintained this course until the aircraft planning and briefing,” the report said. “Mission planning collided with the mountain, 1.8 nautical miles (NM) (3.4 typically included flight plan preparation and review of kilometers) north of the threshold of Runway 12. approaches in accordance with squadron policy; however, the squadron mission briefing guide did not specifically include A U.S. Air Force Accident Investigation Board concluded in approach review. The crew would not have flight-planned for its final accident report that the accident was caused by “a the Dubrovnik leg, because Dubrovnik was not part of the failure of command, air crew error and an improperly designed Change 1 mission,” the report said. approach procedure.” At 1945 hours local time that same day, Change 2 to the The accident aircraft was not equipped with either a cockpit itinerary was transmitted to the 76 AS. This change added voice recorder (CVR) or a flight data recorder (FDR), the report Dubrovnik as a stop on the first day’s itinerary. “It could not said. be confirmed if the [accident] pilots received the information

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 1 Photo: AP/Wide World Photos Wreckage of the U.S. Air Force CT-43A that crashed near Dubrovnik, Croatia, on April 3, 1996, killing U.S. Department of Commerce Secretary Ron Brown and all 34 others on board.

concerning Change 2 that night,” the report said. “The approximately 2200, the copilot called the operations center [accident] copilot’s spouse testified that the copilot received a at Ramstein AB and asked for the latest mission change. “He phone call that evening from the [accident] pilot who requested was verbally briefed on Change 4 and was faxed a copy of that the copilot report to the squadron earlier than planned the Change 4; however, he received only the cover sheet,” the next morning, possibly due to a mission change.” report said.

On the morning of April 2 (the day before the accident flight), Change 4 resulted in the following itinerary for the first day’s the crew prepared for their mission at the squadron, before mission: Zagreb to Tuzla, Bosnia; Tuzla to Split, Croatia; Split departing on a pre-positioning flight to Zagreb. During their to Tuzla; Tuzla to Dubrovnik; and Dubrovnik to Zagreb (Figure planning, the copilot requested a change (Change 3) to the 1, page 3). This change added Split to the itinerary, which was second day’s itinerary, which was approved. [That change required because there was not enough ramp space at Tuzla would allow the crew to return to Zagreb while the commerce for the accident aircraft to stay on the ground for the scheduled secretary’s group was in .] “The copilot also asked a time of seven hours and 20 minutes. Thus, the crew would squadron flight planner to build flight plans for the Dubrovnik drop off their passengers in Tuzla, fly to Split and return later stop,” the report said. “This indicates the pilots were aware of to pick up their passengers in Tuzla before continuing. Change 2 before they departed for Zagreb. They also may have had the opportunity to secure mission planning information While the crew rested in Zagreb, their aircraft was en route for Dubrovnik before they departed Ramstein AB on April 2, from Cairo, Egypt. The pilot of the Cairo flight had received 1996,” the report said. information on the latest change to the accident crew’s mission, the report said. “The Cairo pilot performed some mission The crew departed on another aircraft (flown by another flight preparation for the next day’s missions during this flight, crew) from Ramstein AB at 1232 and arrived in Zagreb at because he knew the [accident] crew was already in crew rest,” 1400. They arrived at approximately 1500 at the hotel where the report said. “He [the Cairo pilot] did not know whether they would remain overnight. Their planned departure time they had already received Change 4 and believed he could was between 0330 and 0400 on the morning of April 3. At help with the planning.”

2 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Itinerary for U.S. Air Force CT-43A, April 3, 1996

SLOVENIA HUNGARY Arad Ljubljana Pecs ROMANIA Zagreb

1 Timisoara CROATIA Rijeka Novi Sad BOSNIA- HERZEGOVINA Tuzla Banja Luka 3 5 SERBIA 2 Sarajevo Numbers refer to the legs scheduled to be flown on Split 4 April 3. No. 4 was the Adriatic Sea accident flight; No. 5 did not take place because of Ploce the accident.

MONTENEGRO Dubrovnik ITALY Titograd

Source: U.S. Air Force Figure 1

The report continued: “The Cairo pilot prepared flight plan (4,800 meters [approximately three miles] visibility) for the information that included proposed routing for three of the approach to Dubrovnik.” five legs (including Tuzla to Dubrovnik). He also provided communications information … and removed the Dubrovnik The accident copilot told the Cairo pilot that “he had received approach procedure, published by Jeppesen Sanderson Inc., a mission change by fax to the hotel earlier, but he had received from the aircraft’s publications kit. He planned to deliver these only the fax cover sheet, with no attached information. They to the [accident] crew when he met with them in Zagreb.” talked for about five minutes,” the report said.

The accident aircraft arrived in Zagreb at 2320. The Cairo pilot On April 3 (the day of the accident flight), the accident crew went to the hotel where the accident crew was staying, arriving assembled in the hotel at approximately 0330, so that they there between approximately 0030 and 0100 [April 3]. “He could report to the aircraft at 0400. The crew contacted the [the Cairo pilot] called the [accident] copilot’s room to arrange operations center at Ramstein AB and was verbally given for the delivery of the copilot’s personal clothing items [which Change 4. “A fax containing this change was retransmitted to were stowed on board the aircraft from Cairo], as well as the hotel,” the report said. the mission change information, planning data and the Dubrovnik instrument-approach procedure,” the report said. At 0403, a weather briefing was faxed from the Ramstein AB weather station to the hotel. “The weather briefing included The report noted: “The Cairo pilot testified that he believed Tuzla, Dubrovnik and Zagreb,” the report said. “The forecast the [accident] copilot was asleep when he called. After he weather for Dubrovnik was: wind 140 degrees at 10 knots called, the Cairo pilot delivered the information to the copilot’s [18.5 kilometers per hour], unrestricted visibility, ceiling room. The Cairo pilot said the copilot was dressed in his jeans broken at 2,500 feet [762 meters] and broken at 8,000 feet [1.5 but looked as if he had just awoke. The Cairo pilot gave the statute miles (SM)/2.4 kilometers], with temporary conditions copilot his clothing and the paperwork he had prepared, of rain. It is not known if the crew received this weather especially noting the unusually high weather requirements briefing prior to departure from the hotel,” the report said.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 3 The 51-minute flight to Tuzla was uneventful, but “while flying the approach at Tuzla, the approach controller notified the crew that they were well left of the final-approach course,” the report said. “The crew responded that they were correcting. After joining the final-approach course, the crew requested a 360- degree turn in order to ‘lose a couple thousand feet,’” the report said.

The crew landed at Tuzla at 0715. The passengers deplaned, and the aircraft departed 37 minutes later, at 0752. The departure was 32 minutes behind schedule.

At 0832, the aircraft arrived at Split and the crew had the aircraft refueled. “They departed Split at 1156, four minutes ahead of schedule; however, the scheduled 40-minute return flight to Tuzla actually took 51 minutes,” the report said. “The extra time was required because the crew flight-planned into Bosnia-Herzegovina through a closed corridor.” The corridor that the crew was required to use added 90 NM (167 kilometers) to the flight.

At 1247, the aircraft landed at Tuzla, where the passengers reboarded. “The [Department of Commerce] added two Croatian nationals to the party, bringing the total passengers to 29,” the report said.

The accident flight departed Tuzla for Dubrovnik at 1355. “After takeoff, the [accident] crew checked in with Tuzla Departure Control, who cleared them to flight (FL) 160 (16,000 feet [4,880 meters]), following the filed standard instrument departure,” the report said. “The crew also asked Tuzla departure for approval to turn left to avoid thunderstorms.”

Boeing 737-100/200 The report continued: “At 1402, radar service for IFO21 was terminated by Tuzla Departure Control, and IFO21 was The short-/medium-haul Boeing 737 first entered service in 1967. The 737-100 seated 115, which was increased instructed to contact Zagreb NATO [North Atlantic Treaty to 130 with the introduction of the 737-200. The twin- Organization] Air Traffic Control (ATC) and monitor MAGIC 737 (U.S. Air Force designation T-43A), has a (the call-sign for a NATO E-3 Airborne Early Warning [AEW] maximum takeoff weight of 52,390 kilograms (115,500 aircraft). They checked in with Zagreb NATO ATC at 1406 pounds) and a maximum cruising speed of 462 knots and were cleared to FL 190 [19,000 feet (5,795 meters)], then (856 kilometers per hour). It has a range of 1,855 nautical to FL 250 [25,000 feet (7,625 meters)].” miles (2,136 miles/3,437 kilometers) with 115 passengers cruising at 33,000 feet (10,060 meters). IFO21 also established contact with the NATO E-3 AEW Source: Jane’s All the World’s Aircraft aircraft, the report said. Good radio communications and radar contact were established with the AEW aircraft (which was responsible for flight monitoring and threat warning in After the crew arrived at their aircraft, they contacted the Croatia and Bosnia-Herzegovina airspace). “The U.S. Air Force Europe (USAFE) Meteorological Service responsibilities of NATO E-3 AEW aircraft do not include (METRO) via high-frequency radio at 0440, the report said. course correction when an aircraft is flying an approach to They received a briefing on the weather for Tuzla (the first an airfield,” the report said. leg of their itinerary) and Zagreb (their alternate for the first leg). At 1404, IFO21 contacted the operations center at Ramstein AB. “[The accident crew] reported their takeoff time from Operating with a call sign of “IFO21,” the accident aircraft Tuzla and asked if there were any mission changes beyond departed Zagreb at 0624. “This was 24 minutes later than the Change 4,” the report said. “They were informed there were planned departure, because the [Department of] Commerce no additional mission changes and were cautioned about the party arrived late,” the report said. possibility of fog at the Dubrovnik airport.” The crew

4 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 acknowledged the weather information and terminated the IFO21 contacted Dubrovnik Approach/Tower at 1446 and was contact. cleared direct to the Kolocep (KLP) NDB [15.9 kilometers (9.9 miles) from the Cavtat (CV) NDB, 11.8 NM from runway The accident crew then contacted USAFE METRO and threshold]. After opposite-direction traffic had been cleared, requested the forecast at Dubrovnik for their planned arrival IFO21 was cleared to descend to 5,000 feet (1,525 meters). time of 1440. “USAFE METRO provided them with the The accident flight began a descent from 10,000 feet following weather information: wind 110 degrees at 12 knots approximately 16 NM (30 kilometers) from KLP. [22 kilometers per hour], ceiling at 500 feet [152 meters] broken, 2,000 feet [610 meters] overcast, 8,000 feet [2,440 meters] “Calculations from groundspeed data indicate the pilot flew overcast, altimeter 29.85 inches of mercury, pressure altitude approximately 224 [knots]–243 knots [414 kilometers per +609 feet [186 meters], temperature +[52 degrees F (11 degrees hour–450 kilometers per hour] indicated airspeed during this C)], [approximately five SM (8,000 meters)] visibility and rain,” descent,” the report said. “Although there are no flight manual the report said. “IFO21 made a pilot weather report to the performance charts that depict this specific descent speed, the USAFE METRO, reporting overall cloudy conditions with little charts for 250 knots [463 kilometers per hour] indicate this indication of thunderstorm activity.” descent would take approximately 16 NM with idle power and up.” As the aircraft flew through Bosnia-Herzegovina airspace en route to Croatia airspace, the AEW aircraft called the crew and The report noted: “Engine anti-ice was ‘on’ at impact. When advised that they were going out of the approved corridor. Under engine anti-ice is on, the operating manual requires an increased Bosnia-Herzegovina flight regulations, there were only three power setting. Use of speed brakes would offset the effect of corridors that aircraft were permitted to use, and one of those the increased power setting. Landing gear down would have — the BEAR corridor — was open only at increased the rate of descent; however, the specific times. The BEAR corridor, which tracking data shows the aircraft descended the flight crew had selected as part of their “The crew’s original in approximately the distance and time that route, was closed at the time of IFO21’s would indicate the landing gear was up. The flight. “The crew’s original flight plan and flight plan and their crew leveled the aircraft for about one their request for the [closed] corridor indicate minute, where the speed slowly decelerated, they were unfamiliar with the corridor times request for the [closed] possibly indicating the power remained of operation,” the report said. corridor indicate they reduced in an attempt to slow the aircraft for [approach] configuration.” IFO21 asked Zagreb NATO ATC to provide were unfamiliar with a radar vector to the approved corridor. At 1452, the crew told Dubrovnik After receiving an initial vector, IFO21 the corridor times Approach/Tower that they were 16 NM resumed navigation along the approved of operation.” from the airport. “They were cleared to corridor. “This unplanned routing added descend to 4,000 feet [1,220 meters] and approximately 15 [minutes]–16 minutes to told to report crossing the KLP beacon,” IFO21’s flight time,” the report said. the report said. “They began the descent and descended through 4,100 feet [1,250 meters] as they crossed KLP. They As the accident crew approached the Bosnia-Herzegovina were still [flying] too fast to fully configure with landing border, “Zagreb NATO ATC transferred control of IFO21 to flaps before beginning the final approach, as required by Air Croatian Zagreb Center civilian controllers (Zagreb Center),” Force directives,” the report said. the report said. Then IFO21 was cleared direct to the Split very high frequency omnidirectional radio range (VOR). At 1450, the pilot of a Croatian aircraft on the ground at “Zagreb Center cleared the [accident flight] to descend to Dubrovnik radioed the accident crew and asked the crew to [FL] 210 (21,000 feet [6,405 meters]), to be level 25 NM contact him on a frequency of 123.47 megahertz (MHz). (This [46 kilometers] before Split,” the report said. was a different frequency from the one being used for the approved tower communication.) The accident aircraft was equipped IFO21 crossed Split at 1434 and was cleared to descend from with two very high frequency (VHF) communication transceivers; FL 210 to FL 140 (14,000 feet [4,270 meters]). “[The accident therefore the crew could communicate with the pilot on the crew] started a normal descent and received further descent ground and simultaneously monitor the tower frequency. clearance from FL 140 to FL 100 [10,000 feet (3,050 meters)] at 1439,” the report said. “After the aircraft reached FL 100 at The pilot on the ground at Dubrovnik had landed one hour 1445, south of Split VOR, Zagreb Center transferred control earlier with the U.S. Ambassador to Croatia and the Prime to Dubrovnik Approach/Tower, a nonradar approach facility. Minister of Croatia, who were awaiting the arrival of Secretary The Dubrovnik Approach/Tower provides air traffic control Brown. The pilot later testified that he told the accident crew services based on vertical, lateral or longitudinal separation, that he had landed one hour earlier, and the weather was at the rather than radar monitoring,” the report said. minimum required for the approach. “He [the pilot on the

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 5 ground] also testified that he told the IFO21 pilot that if he minimums as the NDB approach procedure. Minimums for the had to execute a missed approach, he should proceed to Split,” NDB Runway 12 approach were: minimum descent altitude the report said. “The [Dubrovnik] pilot testified [that] he 2,150 feet (656 meters) and visibility three SM (4.8 kilometers).] conversed with the IFO21 pilot for not more than 20 seconds. [He] also testified that IFO21 acknowledged the conversation.” Investigators could not determine whether the accident pilot or the flight mechanic answered the Dubrovnik pilot’s call The report added: “Other testimony indicated that [the concerning the special circling procedure. “Testimony from Dubrovnik pilot] contacted IFO21 two times and told the the [Dubrovnik] pilot indicated that it was not the same voice [accident] crew about a circling procedure that [he] had used to that was making radio calls on the tower frequency,” the report land. This procedure was not published in the Jeppesen approach said. “Other testimony indicated that the mishap copilot was procedure.” [Although a special circling procedure was not talking on the tower frequency.” depicted on the Dubrovnik NDB Runway 12 approach chart, the Jeppesen chart package for Dubrovnik included a special At the time of the accident, the NDB approach to Runway 12 circling procedure to Runway 30. This procedure had the same (Figure 2) was the only instrument-approach procedure

Illustration of NDB Approach to Runway 12, Cilipi Airport, Dubrovnik, Croatia

318 KLP 10 NM _._ ._.. ._ _. (Morse-code identification)

119 °

397 CV _._. ..._ City of Dubrovnik (Morse-code identification)

119 299 ° ° Approximate accident site 1.8 NM from airport INFORMATION NOT TO SCALE.

Abbreviations: NDB— Nondirectional radio beacon FAF — Final approach fix Cilipi Airport MDA— Minimum descent altitude MAP— Missed-approach point NM — Nautical miles

KLP NDB 4,000 feet FAF CV NDB/Compass locator 119 ° NOT FOR5.2 %NAVIGATION gradient MAP/2,149 feet

MDA/2,150 feet RUNWAY 12 518 feet 11.8 NM 1.9 NM Distance to displaced threshold

Source: Adapted from Accident Investigation Board Report CT-43A 3 April 1996 Dubrovnik, Croatia. This FSF-produced illustration is provided for educational purposes only. This illustration is not approved or intended for navigational purposes by any government or nongovernment entity, including but not limited to civil aviation authorities and commercial companies.

Figure 2

6 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Reconstruction of Final Approach Flown by Accident Crew, U.S. Air Force CT-43A, Dubrovnik, Croatia, April 3, 1996 10

Data labels are altitudes in 5200 feet mean sea level (MSL) from Mode C transponder

4700

3900 5 3200 2600 Kolocep (KLP) nondirectional beacon [NDB] 2300 Initial impact point (final approach fix [FAF]) 2200 at 2,172 feet (662 2200 meters) MSL (Minimum descent Cavtat (CV) [NDB] [compass] locator altitude [MDA] = [missed-approach point (MAP)] 2,150 feet [656 meters] MSL)

0 Runway 12/30

NorthÐSouth Distance from Runway 12 Threshold (nautical miles) 12 NorthÐSouth Runway Distance from *A very high frequency omnidirectional radio range (VOR) has been established at the airport since the accident date. -5 -15 -10 -5 0 5 EastÐWest Distance from Runway 12 Threshold (nautical miles)

Source: U.S. Air Force, International Civil Aviation Organization (ICAO), Jeppesen Sanderson

Figure 3

available at Dubrovnik. The approach uses the KLP NDB to reconstructed using radar surveillance data from Zagreb Center fly the final-approach segment and the CV NDB to define the and two NATO E-3 AEW aircraft. missed-approach point. Data indicate that, at 1453, the accident aircraft crossed KLP, The report noted: “In order to fly the approach, the air crew the FAF, at 1,251 meters (4,100 feet) “and began the approach must be able to maintain positive course guidance and without approach clearance from Dubrovnik [Approach/] determine the missed-approach point. For this approach, Tower,” the report said. “A tower transmission to [the pilot timing may not be used as the primary method to determine on the ground] indicated [that] the tower controller expected the missed-approach point, in accordance with the Jeppesen IFO21 to hold at KLP. However, this transmission was in the approach chart legend; however, timing is recommended as Croatian language, and the crew would not have understood,” a backup in the event of problems with the primary method,” the report said. the report said. Just after IFO21 crossed KLP, another military aircraft asked Because Dubrovnik Approach/Tower is a nonradar facility and Dubrovnik Approach/Tower for the current weather. “The because the accident aircraft was not equipped with a CVR or weather reported to [the other aircraft] was: wind 120 degrees FDR, the final approach flown by the crew (Figure 3) was at 12 knots [22 kilometers per hour], visibility [5 SM (eight

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 7 kilometers)], 492 feet [150 meters] broken, 1,969 feet [600 the aircraft. “After receiving no response, they contacted meters] overcast, altimeter setting 1010 millibars [29.83 inches Dubrovnik City Police, the Croatian Military and the of mercury], temperature [54 degrees F (12 degrees C )], dew Dubrovnik Port Authority,” the report said. “The tower gave point [52 degrees F (11 degrees C)],” the report said. general instructions asking for ships, boats and personnel to conduct the search. Because the approach is over water, this Tracking data from the NATO E-3 AEW aircraft “[indicate that] was where the search began.” IFO21 crossed the [FAF] at approximately 210 knots [389 kilometers per hour] groundspeed,” the report said. “The Zagreb At 1520, Zagreb Center notified Zagreb NATO ATC that IFO21 Center radar shows the aircraft crossing the FAF at 230 knots was overdue. Ten minutes later, Zagreb NATO ATC notified [426 kilometers per hour] groundspeed. Corrections for altitude the NATO Combined Air Operations Center (CAOC) in and wind data (180 degrees at 30 knots [56 kilometers per hour]) Vincenza, Italy, that IFO21 was probably lost in the Dubrovnik result in an indicated airspeed of approximately 209 knots area. The CAOC asked several NATO aircraft in the area to [387 kilometers per hour] based on the NATO E-3 [AEW] attempt radio contact with IFO21. Those radio calls went aircraft tracking data and 228 knots [422 kilometers per hour] unanswered. based on the Zagreb radar data,” the report said. At approximately 1600, the CAOC contacted a French The report noted: “The flight manual also requires an aircraft to military helicopter unit in Ploce, Croatia, which had the be fully configured with landing gear down and landing flaps nearest available helicopters. “The CAOC requested the extended when crossing the [FAF].” Based on these indicated French helicopters prepare to launch and conduct a search airspeeds and the maximum flap airspeeds found in the flight of the area,” the report said. “The French commander called manual, the [accident] aircraft’s flaps were not set for landing his headquarters at Mostar for permission, a process that and would have been between the zero and 10 flap setting normally takes two hours. For this [accident], approval took (normal setting for landing is flaps at 30).” less than an hour. The Croatians did not have helicopters equipped for search-and- At 1454, the copilot of IFO21 called Radar data indicate that rescue (SAR) in the Dubrovnik area.” Dubrovnik Approach/Tower and said, “We’re inside the locator, inbound,” the IFO21 tracked a course The report added: “The local police at report said. IFO21 was then cleared for the Cavtat, Croatia, began their search using approach. of 110 degrees after two police patrols and one patrol boat. crossing KLP, instead of SAR forces searched in the area between Radar data indicate that IFO21 tracked a the suspected crash site at Kolocep Island course of 110 degrees after crossing KLP, tracking the published and the coast between the city of instead of tracking the published course of Dubrovnik and the airport. Zagreb Center 119 degrees. The aircraft maintained this course of 119 degrees. notified Zagreb NATO ATC that an track from KLP to the point of impact. unidentified Croatian civilian source reported a possible aircraft accident on the The accident aircraft descended to 2,200 feet (671 meters), southern tip of Lopud Island. This location was different, “which is consistent with the published minimum descent but it was only two NM [3.7 kilometers] from the original altitude [MDA] of 2,150 feet [656 meters] on the Jeppesen position of the suspected accident site. The [French] approach procedure,” the report said. When the aircraft leveled helicopter crews were advised of the updated location.” at the MDA, it slowed to 140 knots [259 kilometers per hour] groundspeed, which was later calculated as an indicated At 1655, three French helicopters were airborne. When they airspeed of 150 knots [278 kilometers per hour]. Flight manual arrived in the Dubrovnik area, “the initial search area was procedures called for the aircraft to be slowed to final-approach Kolocep Island, the location of the [KLP NDB],” the report airspeed before crossing the FAF, the report said. “The final- said. “Although they searched the island, the helicopters approach target speed from the flight performance manual were unable to reach the highest point, which was obscured calculated for this approach is 133 knots [246 kilometers per by fog. Ceilings were 200 [feet]–300 feet [61 meters–91 hour],” the report said. meters]. Unable to see any wreckage in the vicinity of the island, the helicopters searched Lopud Island, two NM At 1457, “IFO21 impacted a rocky mountainside away, and the area between [KLP NDB] and the airfield,” approximately 1.7 NM [3.1 kilometers] to the left (northeast) the report said. of the extended runway centerline and 1.8 NM [3.3 kilometers] north of the approach end of Runway 12 at Dubrovnik Airport,” The helicopters then searched the area of the instrument the report said. approach to the airfield and the missed-approach route along the coast. “The mountains were obscured by a ceiling at 300 Four minutes after the accident, Dubrovnik Approach/Tower feet, making it impossible to search inland by helicopter,” the personnel made numerous radio calls in an attempt to locate report said. “The French aircraft had the capability to detect

8 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 emergency locator beacons, but never received any The civilian “had heard an explosion at 1500, but did not see transmissions from the crash site.” the wreckage because of poor visibility, which he estimated at 33 feet [10 meters],” the report said. “He had heard the sound As the French helicopters conducted their search, two U.S. of an airplane and then an explosion, but [he] believed the military helicopters and an airborne tanker aircraft launched explosion was probably a grenade or maybe [the noise of a from Brindisi, Italy (about a one-hour flight from Dubrovnik). flying NATO jet]. Because of the poor visibility, he was unable The U.S. helicopter crew had received information that the to see the wreckage until 1800. The [civilian] lived in a remote downed aircraft was a T-34 (a small single-engine U.S. Navy area and did not have a phone. He began a 30-minute drive on training aircraft). “As the helicopters crossed the Adriatic a narrow mountain road in the fog and rain to reach a phone,” Sea, they still believed the aircraft was a T-34,” the report the report said. said. “They learned [the downed aircraft] was a T-43 after they arrived in the search area.” At 1920, five local police located the accident site and radioed police headquarters. “Because it was dark and the terrain The U.S. helicopter crews were not given any information rough, it took an additional 15 [minutes] to 20 minutes to about the downed aircraft’s activities before the accident. reach the site,” the report said. “[The police] were the first “[One of the helicopter pilots] testified that it would have ones on the scene. After they reached the area near the tail been helpful to have known the [downed] aircraft was on section, they found four bodies. The police began looking final approach to Dubrovnik,” the report said. “Also, if they for survivors. The tail section was intact; the main part of had known the aircraft was making an approach, they would the plane was so scattered and so burned that they believed have planned the search to start at the airport and expand to there could be no survivors. Since they did not have any the last known position. The [U.S. helicopters] arrived off special equipment, they called the fire department and the coast of Dubrovnik at 1830,” the report said. ambulance,” the report said.

The accident aircraft was equipped “with a crash position At 1948, the two U.S. military helicopters landed at Dubrovnik indicator (CPI) system [a radio beacon] that broadcasts on to refuel. “Weather was extremely bad with torrential rain, 243.0 MHz, with a range of approximately lightning and estimated 100-foot [31-meter] 80 NM [148 kilometers],” the report said. ceilings,” the report said. After landing, one “The receiving aircraft must be within 50 At 1920, five local police of the helicopter crews “recommended that NM [93 kilometers] to be able to determine the search be called off until the weather the direction of the signal.” located the crash improved,” the report said. “The [CAOC] site and radioed did not agree and directed [that] the search At 1735, a military aircraft that had been would continue.” appointed to be the airborne mission police headquarters. commander received a weak signal on After the helicopters had been refueled, the 243.0 MHz, without directional indication, coordinates of the accident site were given and reported this to the CAOC. This same aircraft reported a to the crews. “The two helicopters remained at the airport stronger signal at 1755. waiting for the clouds covering the mountains to lift; they faced torrential rain, lightning and very low ceilings,” the The two U.S. helicopters began searching the islands off the report said. “As the ceiling would rise a few hundred feet, coast of Dubrovnik. One of the helicopters received a strong they could see blue lights flashing from the emergency signal “because there were no terrain obstructions between [the vehicles at the base of the mountain, then the ceiling would helicopter’s] location and the [accident] site,” the report said. drop again. The ceiling kept them from getting to the [accident] site,” the report said. The second helicopter received only a sporadic signal because of obstructions between the helicopter’s location and the Between 1950 and 2010, 90 additional police arrived at the accident site. “Although both [helicopters] had direction- crash site, set up security and continued looking for survivors. finding capability to locate the beacon, they were unable to At 2030, “despite burning aircraft parts, smell of kerosene, fly toward the indicated beacon location, because the weather poor weather and safety concerns, the Croatian police cleared was too bad. The Dubrovnik Approach/Tower had a VHF a path to the main wreckage,” the report said. “They saw two radio only and was not equipped to receive a beacon individuals in the tail section under debris. After they cleared broadcasting on UHF [ultra high frequency],” the report said. the debris, an airport police officer checked their pulses and felt none. He testified that he was not well informed on how At 1845, “the local police received a call that [a Croatian] to do this [checking for a pulse],” the report said. civilian had seen the [accident] site and had identified the location on top of a mountain … ,” the report said. The civilian At 2130, “one of the individuals in the tail section made a had spotted the wreckage from his house at the base of the breathing sound and had a weak pulse,” the report said. “In mountain where the accident occurred. consultation with a medical team down below the mountain,

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 9 the police administered first aid; they placed a bandage on her At 0450, “the [search team] reported 20 bodies had been [the survivor’s] bleeding leg, turned her on her side to prevent located and marked,” the report said. “No ... survivors were choking, covered her and placed her on a stretcher. The police found.” It took less than 24 hours to recover the remains of did not want to move her down the mountain, because the the aircraft occupants and transport them to a field morgue set weather was so terrible, and they did not want to risk further up at Dubrovnik Airport. injury on the steep path. They believed the best way to move her would be by air,” the report said. An autopsy performed by the U.S. Armed Forces Institute of Pathology revealed that “the cause of death for all but one of Between 2215 and 2230, the crew of one of the U.S. helicopters the [accident aircraft] passengers and crew was blunt force was told about the survivor. A Croatian major (whose affiliation injuries,” the report said. “One crew member died of thermal was not further identified in the report) told the crew, “We inhalation injuries.” An autopsy performed on the cabin crew have an American female; she has a broken spine, and she member who survived the accident but later died revealed that needs immediate medical attention,” the report said. The major she “had extensive and multiple internal, spinal and extremity added, “We are afraid to touch her because we know she will injuries,” the report said. “Any one of several of these injuries die if we try to walk her off the mountain.” The CAOC did not could have been fatal, alone.” want the helicopter to depart until it was certain that the crew was not in any danger, the report said. On April 5, the U.S. Air Force accident investigation team arrived at the accident site and began documenting the At 2236, “one [helicopter] launched with the Croatian major wreckage. It was determined that the aircraft “impacted with on board to attempt to reach the site,” the report said. “The a groundspeed of approximately 138 knots [255 kilometers aircraft made multiple attempts to reach the per hour],” the report said. “IFO21 was site, but clouds and fog were still obscuring in a slight right bank (approximately 11 the area, making it impossible to get close An autopsy performed degrees), configured with flaps set at 30 enough to put the rescue team on the and landing gear down. Exact aircraft ground. Unable to reach the site, [the by the U.S. Armed Forces pitch attitude could not be determined, helicopter] returned to Dubrovnik Airport,” but is estimated to have been near level the report said. Institute of Pathology flight. Flight control analysis of the revealed that “the cause elevators was inconclusive. Evidence The U.S. helicopter pilot told the Croatian indicates that the [accident] pilot hand- major that they would have to get the of death for all but one of flew (autopilot disengaged) the approach survivor off the mountain some other way. to the impact point from the left seat,” “The Croatians began to transport the the [accident aircraft] the report said. survivor down the mountain,” the report passengers and crew was said. “There were no indications of life (no When examining the wreckage, investigators breathing) at this time. At the base of the blunt force injuries,” found “all major structural components were mountain, the [survivor] was put in an located in a debris field approximately 219 ambulance and transported to Dubrovnik the report said. meters (718 feet) long and 141 meters (463 Hospital. At 2355, a Croatian emergency feet) wide,” the report said. “Ground and room physician from the Dubrovnik aerial compass readings indicated that the Hospital, who accompanied [the survivor] in the ambulance, airplane’s initial ground impact marks were oriented along a pronounced her dead,” the report said. magnetic heading of approximately 120 degrees.”

At 0050, the U.S. helicopter crew made multiple unsuccessful Investigators found parts of the fuselage “throughout the attempts to reach the accident site. Finally, at 0145, the wreckage debris field, but most [of it] had been destroyed helicopter “got close enough to drop the three members of by fire,” the report said. “Most of the cockpit structure was the Special Tactics Squad (STS) by rope near the site,” the found near the middle of the debris field and had been report said. “It took an additional 45 minutes for the STS destroyed or severely damaged by fire. A portion of the team to hike to the site, where visibility was reported as less left fuselage/cockpit was found near this location and than 10 feet (three meters). The [team] spent the next several included the pilot’s aft window frame … and the forward hours looking for survivors. There were none.” entry door. The door was in the closed position,” the report said. Other U.S. military personnel arrived at the base of the mountain via ground vehicles at 0400 and set up a communications link The empennage was located and found “upslope from the and base camp. “It took one hour and 15 minutes to walk from initial impact area and oriented on a heading of approximately the base camp to the [accident] site,” the report said. “Visibility 90 degrees,” the report said. “It was upright but resting on was so bad that when [the soldiers] finally were able to see the its left side and the left horizontal-stabilizer tip due to the aircraft tail, they were only [six meters (20 feet)] away.” incline of the hill. This section [extended] from the forward

10 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 break … (near the third fuselage window from the back) to Federal Aviation Regulation[s], Part 121, Certification and the tailcone, which remained attached.” Operation: Domestic, Flag, Supplemental Air Carriers and Commercial Operators of Large Aircraft,” the report said. As A 3.4-meter (11-foot) section of the left wing, beginning at a result, the accident aircraft was not required to be equipped the tip, was found beside the empennage. The inboard section with either a CVR or an FDR. of the wing, “approximately [9.2 meters (30 feet)] long was found adjacent to the similar right-wing section,” the report The report noted that if the accident aircraft had been equipped said. “Except for the inner cylinder and wheels, most of the with a CVR and an FDR, “both may have enabled the [left-main landing gear] remained attached to this left-wing investigators to more clearly identify crew actions during the section.” final phases of flight,” the report said.

A 4.6-meter (15-foot) section of the right wing, beginning at When reviewing the maintenance records of the accident the tip, “was found upslope from the initial impact area and aircraft, investigators determined that “maintenance forms right engine,” the report said. “The wing section had been from March 29 [1996] to April 3, were on board the aircraft at damaged by impact and fire. An inboard wing section the time of the [accident],” the report said. Some of the forms, approximately [9.2 meters] long was one of the last large pieces severely burned and fragmented, were recovered from the of wreckage in the debris field. Much of the lower skin had wreckage. torn away, and a portion of the leading-edge flaps and slats, spoilers and aileron had burned away,” the report said. Investigators found three fragments of maintenance write-ups on the accident aircraft. “On April 2, 1996, there was a notation Examination of the wreckage revealed fire damage that was of what appears to be static on the flight [mechanic’s] characteristic of postimpact fire. Fractured surfaces exhibited interphone,” the report said. “On April 3, 1996, there was a characteristics of overload that were notation of what appears to be ‘a [pitot] static consistent with high-energy impact with light problem.’ There was an additional the ground. There was no preimpact failure A review of other maintenance notation for April 3, 1996, that or separation of the aircraft structure. was unreadable. In each of these three cases, Evidence of fatigue or corrosion that could maintenance records on the corrective action side of the [form] was have precipitated preimpact failure was not the accident aircraft for destroyed or otherwise unreadable.” found on any major component.” 12 months prior to the A review of other maintenance records on the An analysis of the crash forces determined accident aircraft for 12 months prior to the that the accident was nonsurvivable. accident indicated no accident indicated no discrepancies related to “Forensic analysis of injuries estimates the discrepancies related to the accident. “A thorough review of the spare- decelerative forces in the forward portion parts request report (a logbook for tracking of the aircraft were approximately 100 the accident. parts) revealed no significant trends or [Gs]–150 Gs (one G is a unit measuring recurring maintenance malfunctions for the the inertial stress applied against a body [accident] aircraft,” the report said. “The by the force of Earth’s gravity), and the decelerative forces in engine-condition monitoring program revealed no abnormalities the tail section, experiencing the least amount of force, to be in engine performance. Aircraft historical records indicated no approximately 50 [Gs]–80 Gs, the upper limit of recurring maintenance problems with engine, airframe or survivability,” the report said. avionics systems.”

The report noted: “There was no evidence of emergency egress The accident aircraft had been maintained by Boeing or use of life support equipment; all injuries were fatal or contractors based at Ramstein AB since 1992. “A review of incapacitating.” personnel records revealed that all contractor personnel were U.S. Federal Aviation Administration (FAA)–certified airframe Investigators reviewed the history and maintenance records and powerplant technicians and were authorized to clear of the accident aircraft, which was one of two CT-43As in the aircraft grounding discrepancies,” the report said. “All initial U.S. Air Force inventory that were originally used for training and recurring training was current. Interviews with the navigators. In 1992, the accident aircraft was modified to carry [maintenance] manager and lead mechanic at Ramstein AB 53 passengers and assigned to the 76 AS at Ramstein AB. “A revealed a high level of attention to detail and sound crew of six normally operates the aircraft: two pilots, a flight maintenance practices.” mechanic and three in-flight passenger service specialists,” the report said. The report noted: “The [accident] aircraft flew a total of 103.5 hours and 48 sorties with a 98.6 percent mission-capable rate The accident aircraft “was a U.S. government aircraft operated since its last inspection. A review of unscheduled maintenance as a public use aircraft and, therefore, was exempt from U.S. for February 1996 indicated the contractor replaced a pressure

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 11 controller … and a vertical gyro … . The contractor reported teardown and analysis. These items were burned and seven discrepancies in March 1996, none of which showed damaged. Physical evidence provided no definite conclusions any correlation to the [accident].” for the GPWS control display. The GPWS receiver/ transmitter suffered extensive internal damage, prohibiting Both engines from the accident aircraft were recovered and any functional testing of mechanical parts from which to examined. “Engine analysis indicated both engines were derive data,” the report said. running at similar speeds, significantly above idle,” the report said. “Analysis of the engine number one fuel-control unit An analysis was conducted to determine if the GPWS could indicates a high power setting was selected for the number have warned the accident crew about the terrain proximity. one (left) engine.” “The [accident] flight profile indicates a groundspeed of 140 knots [259 kilometers per hour] with the aircraft in level flight The report said that the damage to both engines “appears at an altitude of [668 meters (2,191 feet)] above the terrain,” similar in magnitude between the two engines, indicating a the report said. “The relevant portion of the receiver/ proportionate level of rotor speed between the two engines. transmitter circuitry was simulated using a computer-based … There was no indication of preimpact malfunction. There program … .” were no indications of fire external to the engine or burn on any visible case. There were no indications of bird The report concluded: “Analysis showed the warning profile remains in the engines. Both engine thrust reversers were was never penetrated — with the terrain profile, aircraft found in the stowed position, indicating they did not deploy configuration and flight path as described, no warning from in flight.” the GPWS would have been produced. This is consistent with the GPWS’s design.” The report noted that the high engine power at impact “might indicate one of three things: The crew may have been initiating A review of the accident aircraft’s maintenance records for a missed approach, the crew [may have been] responding to the 12 months preceding the accident flight revealed no visual recognition of the terrain or the crew was responding to discrepancies in the aircraft’s attitude heading reference system an aural signal from the ground-proximity warning system (AHRS). The AHRS provides continuous attitude (pitch and [GPWS],” the report said. roll) and heading information for display on the:

“A thorough review of the spare-part request and maintenance • Pilot’s attitude direction indicator (ADI); documentation revealed no discrepancies for the [GPWS] control display and receiver/transmitter from August 1992 • Pilot’s horizontal situation indicator (HSI); to April 1996,” the report said. “The GPWS control panel and receiver/transmitter were sent to Rockwell Collins for • Pilot’s radio magnetic indicator (RMI);

CT-43A Ground-proximity Warning be between 519 meters and 549 meters [1,700 feet and 1,800 feet] per minute, and never reached the 2,000-feet-per-minute System (GPWS) Warning Profiles warning limit; Were Not Activated Mode 3. Excessive barometric altitude sink rate or loss with flaps and gear not in the landing configuration: No warning Based on the flight path, terrain profile and the accident aircraft’s profile penetration because the flaps and gear were in the configuration and groundspeed, Rockwell-Collins engineers landing configuration; concluded that the none of the GPWS’s six warning profiles would have been activated. Following are the warning modes Mode 4. Insufficient height above terrain without flaps and gear of the Rockwell-Collins model FPC-75 GPWS and conclusions in the landing configuration: No warning profile penetration about why each mode did not activate: because the flaps and gear were in the landing configuration; and, Mode 1. Excessive barometric altitude sink rate: No warning profile penetration because the aircraft was in level flight; Mode 5. Excessive below-glideslope deviation: No warning profile penetration because no glideslope signal was available. Mode 2A. Excessive closure rate with flaps not in landing configuration: No warning profile penetration because the flaps “This was an unfortunate set of circumstances that defeated were in the landing configuration; the design and utility of the GPWS,” said Roger Southgate, a Rockwell-Collins engineer who helped conduct the post- Mode 2B. Excessive closure rate, flaps in the landing accident investigation of the GPWS. “GPWS does have the configuration: No warning profile penetration because 2,000 ability to provide valid and timely warning for terrain avoidance feet [610 meters] per minute is the lowest closure rate warned and clearance, but it is not a predictive device, it cannot see by the device. The rate of increasing terrain was determined to ahead of the aircraft.”♦

12 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Photo: AP/Wide World Photos U.S. Army investigators walk toward wreckage of rear fuselage and empennage of U.S. Air Force CT-43A that crashed on approach to Dubrovnik, Croatia.

• Pilot’s bearing distance heading indicator (BDHI); and, information. A complete teardown analysis of all recovered instruments was accomplished.” • Copilot’s BDHI. The accident aircraft was equipped with two inertial navigation The cockpit instruments recovered from the wreckage had systems (INSs) “that derived present position, groundspeed, sustained severe fire damage. Nevertheless, investigators were heading and other flight parameters from display on two able to determine the aircraft’s heading, roll and bearing separate control/display units (CDUs) located in the pilot’s information from the recovered instrumentation. “Nothing was forward control panel,” the report said. “Operation of each noted during analysis that indicated instrument or instrument INS is controlled by a mode selector unit and a CDU. Display system failure prior to impact or loss of input signal,” the report of position and other flight parameters plus system operating said. status [are] displayed on the CDU,” the report said.

When examined, “the ADI indicated a right-wing bank of Investigators recovered and examined both CDU and INS approximately five degrees,” the report said. “The pilot’s HSI units. When the first CDU was examined, an analysis and BDHI showed a course bearing between 115 degrees determined that “the display selector switch was set to the and 119 degrees. The RMI front glass, bezel, switch knobs, cross-track/track-angle error position and the automatic manual compass card and bearing pointers were missing. The remote (AMR) switch was on the automatic (A) position,” the teardown revealed the RMI needle was either 115 degrees or report said. The second CDU was examined and “the display 295 degrees … .” selector switch was set to the heading/drift-angle position and the AMR switch was set to the ‘A’ position.” The report noted: “The mach/airspeed indicator, altimeters, radio altimeters and other instruments were severely damaged The first INS unit was examined and declared completely by impact and postimpact fire and provided no useful destroyed. The second INS unit was examined and found to

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 13 A Primer: the Nondirectional The NDB radio signal is also subject to interference created by weather conditions, the presence of other radio transmitters Radio Beacon (NDB) and by geographically induced phenomena associated with mountainous terrain or large expanses of water, all of which Two nondirectional radio beacons (NDBs) were the primary can produce erroneous needle indications. navigational aids (NAVAIDs) for the instrument-approach procedure to land on Runway 12 at Cilipi Airport, Dubrovnik, An NDB can be an en route NAVAID, and by using a second Croatia, the destination of the U.S. Air Force CT-43A accident NDB radio signal (or the signal from another radio NAVAID), airplane. the pilot can “fix” the aircraft’s position in relation to the two An NDB is a ground-based radio NAVAID that transmits radio signals. frequency (rf) energy on the low-frequency (30 kilohertz [kHz]– 300 kHz) or medium-frequency (300 kHz–3000 kHz) portions A pilot can also fly an NDB instrument approach, which specifies of the radio spectrum. (In the United States, NDBs operate on various procedures, including altitudes, turns, radio frequencies frequencies between 190 kHz and 535 kHz; in Europe, the and so forth, that the pilot must follow to land an aircraft in frequency can be as high as 625 kHz). instrument meteorological conditions (IMC). The NDB approach does not provide precision vertical guidance for the descent or Developed in the late 1920s, the NDB is one of the oldest precision horizontal (lateral) guidance for runway alignment. NAVAIDs in use. Although modern NDBs are more Thus, situational awareness by the pilot is especially important technologically advanced than those of the 1920s, they all in an NDB approach. operate on the same basic principle: A transmitter converts electrical energy into rf energy and delivers the rf energy to an In elementary terms, the objective of an NDB instrument omnidirectional broadcasting antenna. A modern automatic approach — as is that of other types of instrument approaches direction finder (ADF) aircraft receiver determines the direction during conditions of restricted visibility — is to allow the pilot to the NDB and conveys that information by a pointer on the to descend the aircraft to the lowest possible safe altitude face of a round display instrument surrounded by an adjustable (which is determined by factors such as terrain and the type compass rose. (In the early days of NDB navigation, the pilot of instrument approach) so that the pilot has the best hand-cranked the aircraft’s receiving antenna to determine the opportunity to visually identify the airport, continue the direction of the NDB in relation to the aircraft). approach and land the aircraft. After descending to the lowest safe altitude (minimum descent altitude [MDA] on an NDB By following the direction of the needle, the pilot can fly the instrument approach), if the pilot does not visually identify aircraft to a specific beacon, which is identified by a Morse- the airport by the time the missed-approach point (MAP) is code identifier transmitted by the NDB. Nevertheless, the pilot reached, then the pilot must follow specific procedures to usually must adjust the aircraft’s heading to the NDB to abandon the approach. In the Dubrovnik accident, a second compensate for the effects of wind, so that the most direct NDB identified the MAP. Where authorized in other NDB course is maintained. Otherwise, rather than following a direct procedures, timing can be used to identify the MAP based course to the NDB, the aircraft’s course can curve as the pilot on a specific groundspeed from the final approach fix to the “homes” on the NDB radio signal. MAP.

have been operating for one hour and 12 minutes before impact. degrees from the top of the case, i.e., six degrees right of the The geographical coordinates stored in this unit at the time of six o’clock position, confirming that the ADF was tuned to power loss were recovered and indicated that “the inertial the KLP [NDB] at the time of impact,” the report said. [The navigation equipment on the [accident] aircraft was performing difference between 316 kHz and 318 kHz was not considered satisfactorily and within specifications (maximum allowable to have significantly affected reception of the KLP NDB for drift of two NM [3.7 kilometers] per hour in the navigation navigation purposes.] mode) at the time of impact,” the report said. The aircraft was also equipped with a compass adapter, which The accident aircraft was equipped with one low-frequency “receives digital inputs from the [AHRS] and the [INS] and radio automatic direction finder (ADF) system. “Circuits in converts them to analog outputs for the pilot’s HSI, RMI, the [ADF] receiver determine the bearing of radio stations and BDHI and the copilot’s BDHI and autopilot,” the report said. transmit the information to the pilot’s [RMI],” the report said. “Teardown inspection of the compass adapter indicated the “The RMI is located on the pilot’s forward instrument panel.” aircraft heading was between 116.1 [degrees] and 116.4 degrees. These outputs correspond with RMI, HSI and BDHI Investigators analyzed the ADF receiver to determine the teardown reports that suggested, from physical evidence, the frequency selected at the time of impact. “The tuning synchro, heading at impact was between 115 [degrees] and 119 which is directly slaved from the ADF control panel, indicated degrees.” a tuned frequency of 316 kilohertz [kHz],” the report said. “(KLP frequency is 318 kHz.) The output synchro to the A CPI was also installed on the aircraft. “The CPI system pilot’s RMI indicated the bearing needle was pointing at 174 consists of a control panel on the cockpit forward overhead

14 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 panel, four external sensing switches, a radio beacon dispenser The background and qualifications of the flight crew were located on the vertical tail section and an airfoil containing a reviewed. The accident pilot had 2,942 total flying hours, with radio beacon, batteries and transmitting antenna,” the report 582 hours in the CT-43A. His flight times in the CT-43A during said. the 30-, 60- and 90-day periods prior to the accident flight were 37.0 hours, 77.5 hours and 87.6 hours, respectively. When investigators examined the CPI on the accident aircraft, they found that it had partially deployed. “It [the CPI] remained The pilot completed his undergraduate pilot training instrument attached to the vertical portion of the tail during the accident,” check in 1987. He then “upgraded from KC-135Q [the military the report said. tanker version of the Boeing 707] copilot through aircraft commander, instructor and evaluator pilot positions over the The report noted: “The resulting location of the CPI after the next six years,” the report said. “The pilot had approximately accident placed it between a steep section of the mountain to 464 instructor hours and 36 evaluator hours in the KC-135.” the south and southwest and the vertical section of the aircraft tail to the north and northeast. This blocked the CPI signal in The pilot received his initial T-43 qualification in 1994, and every direction except to the northwest and the southeast. An was assigned to the 76 AS at Ramstein AB. “The squadron interview with the [SAR helicopter] pilot confirmed the CPI commander in place at the time the pilot arrived at Ramstein emitted a distress signal on the international emergency [AB] in 1994 indicated the pilot did not display adequate frequency.” procedural knowledge for upgrade to aircraft commander,” the report said. Investigators also performed a teardown analysis of the CPI battery pack and found it in good condition. “The battery’s The squadron commander “did not upgrade the pilot during power was depleted, indicating that it activated the airfoil the eight months they were both assigned to the 76 AS. release mechanism,” the report said. “After charging the unit However, he [the squadron commander] did not document overnight, it was tested and passed all operational criteria.” his concerns and did not note substandard performance in

Table 1 Table 2 Nondirectional Radio Beacons (NDBs) Nondirectional Radio Beacon (NDB) By World Region Approaches, by World Region

Region Number of NDBs* Region Number of NDB Approaches* Africa 1,821 Africa 60 Canada (including Alaska) 1,284 Canada 237 Eastern Europe 2,681 Eastern Europe 177 Europe 2,734 Europe 287 Latin America 268 Latin America 54 Middle East 919 Middle East 68 Pacific 634 Pacific 71 South America 1,204 South America 200 South Pacific 1,219 South Pacific 81 United States 3,738 United States 1,578 Total 16,502 Total 2,813

* Includes Terminal, Approach and En-route NDBs. * Individual procedure Source: Jeppesen Sanderson Inc. Source: Jeppesen Sanderson Inc.

NDBs are grouped by power-output range, with the power designated for en route navigation) located throughout the output determining the distance that the signal can be received world, with 3,738 of them located in the United States. Some reliably, ranging from less than 25 watts and 15 nautical miles 2,813 individual NDB approach procedures are identified (NM) for compass locators, to 2,000-watt, high-power worldwide, with 1,578 of them located in the United States. In transmitters that have service ranges of 75 NM. each category, data show the United States with the greatest numbers. Statistics supplied by Jeppesen Sanderson Inc., based on data in “NavDat,” the company’s electronic navigation data NDB statistics by world region are shown for NAVAIDs in Table base, indicate that there are 16,502 NDBs (most are 1 and for approaches in Table 2.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 15 Many pilots do not fly NDB approaches frequently. As part of a horizontal cross-bars on a single instrument display, 1995 study conducted by Earl L. Wiener, Ph.D., and Rebecca respectively. D. Chute, and sponsored by the U.S. National Aeronautics and Space Administration (NASA), 147 commercial transport pilots The pilot operates the flight controls to center the cross-bars. who were transitioning to the Boeing 757 airplane were asked Undesired deviations are indicated by the localizer and to report the number of NDB approaches that they had glideslope crossbars and alert the pilot to make the appropriate conducted in the previous calendar year. Nearly 60 percent of corrections. Moreover, the aircraft’s autopilot can be coupled the pilots who responded said that they had not flown an NDB to the aircraft’s ILS receiver and other aircraft systems, so that approach within the previous calendar year. Of those who the autopilot will fly most of the approach, and the pilot will responded, only 10 percent had conducted six or more NDB land the aircraft. With additional equipment on the ground and approaches during that period. on the aircraft, and the appropriate pilot training, a transport- category airplane can be landed automatically — without a pilot Some airports use an NDB as the primary approach NAVAID touching the controls. or as a supplementary approach NAVAID because NDBs are less expensive to purchase and less difficult to maintain An ILS usually permits the pilot to descend the aircraft to a lower than precision landing systems. Charles Whitney, chief — but still-safe — altitude than an NDB approach, thus providing engineer of Southern Avionics Co., which manufactures a better opportunity to visually identify the runway in restricted- NDBs, said that “NDBs are used for backup,” in countries visibility conditions. The precise ILS guidance also reduces pilot where instrument landing system (ILS) facilities are subject workload during a critical and demanding phase of flight. The to frequent breakdowns or disruptions. He said that as much very high frequency of the radio spectrum used by the ILS is as 85 percent of the company’s NDB products are exported also less vulnerable to weather-related interference than the to other countries from the company’s plant in Beaumont, NDB, and careful design of each ILS aims to reduce the likelihood , U.S. of problems caused by other rf interference and geographical influences. Nevertheless, despite the advantages of an ILS An NDB system costs between US$20,000 and $40,000, approach, an NDB approach is safe when performed properly. depending on the transmitter’s power output, in addition to installation costs, Whitney said. A basic ILS — with a low-power glideslope and localizer — costs $65,000 to $70,000, in addition to installation costs, An ILS is preferable to an NDB-based approach because, unlike according to Rich Viets, manager of technical marketing at the NBD, the ILS provides precision approach guidance. An ILS Wilcox Electric Inc., Kansas City, Missouri, U.S., which provides precise information about the aircraft’s position in manufactures ILSs. Viets said that a much more advanced ILS relation to the glideslope (vertical guidance) and the localizer system could cost between $500,000 and $1,000,000, (horizontal guidance), which are displayed as vertical and excluding installation. — Editorial Staff

the pilot’s performance reports. This squadron commander proficiency,” the report said. “Additionally, [an NDB] also selected the pilot for the 76 AS Pilot of the Quarter, and instrument approach was evaluated during the pilot’s first did not tell his replacement about his concerns,” the report evaluation [in] October 1995.” said. The report concluded: “The pilot was fully qualified for the The report noted: “A CT-43A instructor/evaluator pilot who flying activities he was performing at the time of the flew with the [accident] pilot from the time the [accident] pilot [accident].” arrived at the 76 AS until February 1996 noted no problems during the [accident] pilot’s normal upgrade programs. He felt The accident copilot had 2,835 total flying hours, with 1,676 the [accident] pilot had consistently improved since his arrival hours in the CT-43A. His flight times in the 30-, 60- and 90- at Ramstein [AB].” day periods prior to the accident were 20.4 hours, 57.2 hours and 70.7 hours, respectively. The copilot completed his In 1995, the pilot was upgraded to aircraft commander. He undergraduate pilot training in 1989. In 1990, he completed was granted a waiver in January 1996, “to upgrade to instructor qualification in the CT-43A “and upgraded to aircraft with less than the required 100 hours minimum flying time as commander over the next two years,” the report said. an aircraft commander,” the report said. In February 1996, the pilot was granted a second waiver and was allowed to upgrade In 1993, the copilot was qualified in the C-141B and flew 960 to evaluator pilot. hours in that aircraft. “Following assignment to the 76 AS, the copilot completed a local first pilot requalification [in] 1995,” The pilot’s training records were reviewed for proficiency at the report said. “During the series of flights planned from April NDB approaches. During his initial qualification in 1994, he 3–5, 1996, the copilot was scheduled for a checkride to performed three NDB approaches satisfactorily. “At complete his upgrade to aircraft commander. However, his Ramstein, during both first pilot and instructor pilot upgrade training records indicate he had not completed the 76 AS level training programs, the pilot flew [NDB] approaches to 2 upgrade training book as required. The 76 AS training

16 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 manager could not say whether this training had been “At the time of the [accident], the crew was 11 hours and 27 completed but not documented,” the report said. minutes into their duty day based on a reporting time of 0330,” the report said. “The total planned crew-duty time for the day The copilot’s training records were reviewed for proficiency was 13-1/2 hours (0330 show time at Zagreb to a planned 1700 at NDB approaches. “[NDB] instrument-approach training was landing at Zagreb).” documented during requalification training flights [in 1995] in which [NDB] approaches were flown to proficiency,” the The weather conditions during the accident flight were report said. “The copilot was fully qualified for the flying reviewed. On the day of the flight, “a low-pressure system activities he was conducting at the time of the [accident].” dominated the Mediterranean region,” the report said. “The low pressure caused widespread cloudy conditions throughout The activities of the flight crew prior to the accident were the area with light rain, rain showers and very isolated reviewed. “Associates and immediate family members of the thunderstorms. The European Meteorological Satellite … flight-deck crew did not indicate any unusual habits, behavior image … shows most of the former under dense or stress,” the report said. “Specifically, there were no known cloud cover. The image shows some enhanced cloud tops problems or peculiarities with diet, alcohol or medication use, indicating thunderstorms.” sleep/wake cycle, change in usual physical activities, unusually stressful situations at home or work, indications of fatigue or The weather briefing faxed by the Ramstein AB weather unusual changes in moods.” station to the accident crew’s hotel forecast overall cloudy skies for their entire route, “isolated thunderstorms with A postmortem toxicology analysis of the crew was “negative maximum tops of 35,000 feet [10,675 meters], moderate clear for medications, illicit drugs or alcohol,” the report said. “There air turbulence from surface to 10,000 feet, light rime/mixed were no significant pre-existing diseases in the air crew.” icing from 10,000 feet to 18,000 feet [5,490 meters] and occasional rain or snow showers,” the report said. When investigators reviewed the rest periods for the crew, they found that “complete crew rest histories for the crew could The forecast for Dubrovnik for the accident crew’s estimated not be determined,” the report said. “Prior time of arrival was: “forecast winds — 140 to departure from Ramstein AB, both pilots degrees at 10 knots [18.5 kilometers per received their usual amount of sleep. The “A postmortem hour]; visibility — unrestricted; sky crew arrived in Zagreb (there are no time condition — broken at 2,500 feet [762 zone changes between Ramstein and toxicology analysis of meters] (ceiling) and broken at 8,000 feet Zagreb) via a … pre-positioning flight on the crew was “negative [2,440 meters]; altimeter setting — 29.58 April 2, 1996, at 1400 and entered crew rest. inches of mercury; pressure altitude of [+] Afternoon and evening activities, as well for medications, illicit 860 feet [262 meters]; temperature — [54 as the times the crew went to sleep, are degrees F (12 degrees C)]; and temporary unknown,” the report said. drugs or alcohol.” conditions of rain,” the report said.

The report noted: “However, according to While en route to Dubrovnik, the accident testimony, when air crews on the road had a planned morning crew transmitted a pilot report (PIREP) to USAFE METRO. departure the next day, they would typically eat dinner and go “The PIREP coincides with all other data,” the report said. to sleep about 2100 or 2200.” “The crew reported conditions as overall cloudy and wet with little indication of thunderstorm activity. The IFO21 The copilot had two interruptions during his rest period. The crew then asked if METRO expected any changes in the first occurred when he called the Ramstein operations center future weather. USAFE METRO reported little change for mission changes at 2200. “A second interruption occurred expected.” when, at the copilot’s request, the Cairo flight pilot contacted the copilot between 0030 and 0200,” the report said. Investigators reviewed thunderstorm activity that occurred during the accident flight. “Lightning stroke data from 1500 The report added: “There was no indication the pilot’s crew shows weak thunderstorm activity (two [strokes]–three strokes rest was interrupted. Air crews would typically begin the next from 1430–1500) to the north and south of Dubrovnik,” the crew-duty day when they assembled at the hotel two and one- report said. “This would be consistent with the reports of half hours prior to the planned takeoff. Therefore, for a planned thunderstorms by some eyewitnesses. There were differing takeoff of 0600, the [accident] crew would have begun the reports concerning wind, clouds, thunderstorm activity and crew duty day at 0330, affording them an opportunity for at the amount and intensity of rain. The reports range from a least 12 hours of crew rest.” light rain to a storm locals called the worst in years.”

The accident crew would have been limited to 18 hours from The weather observations for Dubrovnik from 1200 to 1400 the scheduled crew reporting time to engine shutdown time. indicated that a rain shower had passed through the area with

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 17 thunderstorm clouds. “The tower controller at Dubrovnik never The report noted: “No effects from the local radio frequency saw lightning [or] heard thunder,” the report said. environment were observed during any of the flight tests at Dubrovnik. There are no indications that HIRF contributed to The official weather observation for Dubrovnik at the time of the IFO21 accident.” the accident was: “winds 120 degrees at 12 knots; visibility … of [five SM] with light rain; sky condition — 400 feet [122 The possibility that lightning could have interfered with the meters] broken … overcast at 2,000 feet … ; temperature — accident aircraft’s ADF receiver was examined. “Due to the [54 degrees F (12 degrees C)]; dew point temperature — [52 straight flight path of IFO21 for the extended period of the degrees F (11 degrees C)]; altimeter setting: 29.83 inches of final approach, an external short-term electrical disturbance, mercury,” the report said. such as lightning, in the vicinity of the flight path of IFO21 would not explain the extended course variation,” the report The weather deteriorated significantly in the hour following said. the accident, the report said. “At 1600, the Dubrovnik official observation was: Winds 120 degrees at 16 knots [30 kilometers Investigators examined the possibility that coastal bending per hour]; visibility [0.6 SM (1,000 meters)] with rain showers; could have affected the quality of the signals transmitted from sky condition 300 feet [91.5 meters] overcast. The conditions both the KLP and CV radio beacons. “Ground waves from a changed little over the next few hours,” the report said. transmitter that pass over sea water incur less loss than waves that pass over land areas,” the report said. “As a result, in the Investigators also reviewed the upper-air wind data for the vicinity of the transition region between land and water (at Dubrovnik area during the time of the accident flight. The the coast line), the wave front will no longer be perpendicular wind data were based “on the Brindisi, Italy, upper-air to a line joining the transmitter and receiver, due to the sounding and interpretation of all available data,” the report increased loss over land. This phenomenon is termed coastal said. “The difference from Brindisi is due to the local effects bending.” of the mountains near Dubrovnik. Winds: 110 feet [33.5 meters] — 130 degrees at 13 knots [24 kilometers per hour]; The report continued: “Coastal bending can manifest itself in 400 feet — 150 degrees at 21 knots [39 kilometers per hour]; the form of bearing error in an ADF system. This type of 3,000 feet [915 meters] — 160 degrees at 25 knots [46 anomaly could exist near the accident area due to the location kilometers per hour]; 5,000 feet [1,525 meters] — 170 of the coastline of the Adriatic Sea. This anomaly was seen in degrees at 24 knots [44 kilometers per hour]. There were no a small needle shift crossing the [CV NDB]. However, reports [or] indication of wind shear … ,” the report said. propagation anomalies would not explain the specific straight route of flight taken by the crew of IFO21.” The accuracy of the navigational aids (NAVAIDs) used for the instrument-approach procedure at Dubrovnik was Possible sources of EMI from on board the accident aircraft reviewed. Five days after the accident, U.S. Federal Aviation were examined. “Emissions from portable electronic devices Administration (FAA) flight-check inspectors conducted a special flight inspection of both the KLP and CV radio beacons. Both NAVAIDs were found to be satisfactory. “FSF CFIT Checklist”

The investigation also reviewed the possibility that the Flight Safety Foundation (FSF) has designed a controlled- following types of electromagnetic environmental effects flight-into-terrain (CFIT) risk-assessment safety tool as part might have contributed to the accident: “High-intensity of its international program to reduce CFIT accidents. Listed radiation fields (HIRF); lightning effects; coastal bending of below are some of the risk factors that were identified in the “FSF CFIT Checklist” (following page 25) that are the [KLP] 318 [kHz] or [CV] 397 [kHz] [NDB] signals; applicable to the Dubrovnik accident: electromagnetic interference (EMI) sources; NDB signal reflection either by small-aperture reflectors or terrain; and • No radar coverage available for the approach; mistakenly tuning to an NDB other than KLP or CV,” the report said. • Airport located in or near mountainous terrain; • Nondirectional radio beacon approach; In reviewing the area for HIRF, investigators examined the possibility that high-power transmitters in the vicinity of the • Controllers and pilots speak different primary final-approach course interfered with the accident aircraft’s languages; avionics. “An examination of available information indicates • Nonscheduled operation; that the most powerful emissions in the vicinity of Dubrovnik are associated with local television transmissions,” the report • Arrival airport in Eastern Europe; and, said. “The emissions from these transmitters along the IFO21 ♦ flight path are present for all other aircraft approaching Runway • Instrument meteorological conditions during approach. 12 at Dubrovnik, and no HIRF problems have been reported.”

18 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 (PEDs), such as notebook computers, CD [compact disc] Investigators reviewed the instrument-approach chart used by players, cellular telephones and hand-held computer games the accident crew during its approach and the design of the were considered as a possible on-board source of EMI,” the instrument-approach procedure. “Jeppesen Sanderson Inc. report said. “At least one PED (a notebook computer) was publishes instrument-approach procedures from the host-nation found in the accident debris. Analysis, ground testing and flight procedures after reformatting and translating,” the report said. testing indicated that PED emissions did not interfere with the “Jeppesen also adds terrain data, as necessary. However, they CT-43A navigational aids.” do not review or approve the adequacy, reliability, accuracy or safety of the procedures. The mountain struck by the aircraft EMI sources from outside the accident aircraft were was depicted on the approach procedure by Jeppesen considered. These EMI sources were “electrical disturbances Sanderson Inc.” associated with an electrical power plant near the accident site and signals from other [NDBs] either behind (up-range) IFO21 The report described the approach procedure: “The instrument- or in front (down-range) of IFO21,” the report said. “Potential approach procedure identifies the [KLP NDB] as the primary interference to the ADF receiver from three mechanisms [was] navigational aid for this approach. KLP defines the final- examined: corona discharge, power-line carrier signaling and approach holding fix [FAF] and the final-approach course. The reradiation of the NDB signal by the power lines. There is no final-approach course is the 119-degree bearing (southeast) indication that these phenomena affected the CT-43A from KLP to the runway. … The missed-approach point for navigational equipment. It was observed that the distances were the Dubrovnik approach is defined by the [CV] locator. The too far, the frequencies too dissimilar or both. During flight missed-approach procedure requires an immediate right turn tests, no [EMI] was observed.” and a climb to 4,000 feet.”

The possibility that the CV NDB signal could have reflected An aircraft must have two ADF receivers to fly the approach, off a microwave antenna near the accident site or off the the report said. “One ADF must be tuned to the [KLP NDB] mountain was examined. “In either case, the reflected signal to identify the [FAF] and provide continuous course would have been too weak in comparison to guidance to the runway,” the report said. the signal received directly from CV to have “Simultaneously, another ADF must be contributed to the accident,” the report said. An aircraft must have tuned to the [CV] locator to identify “Flight tests supported this determination; the missed-approach point. With this no interference was observed.” two ADF receivers to configuration, the pilot can continuously monitor the final-approach course and also Investigators also considered the possibility fly the Dubrovnik identify the location of the missed- that the accident crew might have mistakenly approach. approach point. The aircraft did not have tuned their only on-board ADF receiver to a the two ADF receivers required to fly the frequency other than KLP or CV. “An Dubrovnik approach in instrument examination of the frequencies of other conditions.” [NDBs] in the area and their expected signal strength showed that several [were] capable of being received along the flight The report noted: “The Jeppesen approach procedure for path of IFO21,” the report said. “An examination of the aircraft’s Dubrovnik does not specifically indicate what type of actual route of flight prior to KLP passage shows an obvious equipment is necessary to fly the entire procedure. However, transition from navigation via the Split [VOR] to navigation [U.S.] Air Force pilots are responsible for recognizing the via the KLP NDB shown by the right turn and radial flight to factors which go into an approach and determining if the KLP, direct passage over KLP, followed by an outbound radial aircraft is properly equipped. If the crew had accurately directly to the impact point.” reviewed the approach procedure, they would have recognized that two ADF receivers were required.” The report concluded: “The route of flight taken and the condition of instruments examined after the accident indicated Investigators were unable to determine how the accident crew KLP was successfully tuned on the ADF.” had planned to identify the missed-approach point, but they believed the crew might have used timing as a back-up. The The NDB approach flown by the accident crew was the only pilot’s clock was recovered from the wreckage. “The minute instrument-approach procedure available for Dubrovnik. “The recording hand and the sweep second hand … were stopped at Dubrovnik airport was formerly served by an instrument five minutes and 50 seconds, indicating the pilot may have landing system (ILS) for precision approaches, a [VOR] for attempted to time to the missed-approach point,” the report nonprecision approaches and a third NDB [in addition to KLP said. and CV],” the report said. “The Croatian authorities reported the VOR, ILS and one NDB were stolen or destroyed during The report noted that “the actual time from the [FAF] to the the conflict period between 1992 and 1995. The stolen NDB impact point was approximately four minutes, indicating the was later replaced.” pilot started the clock before the [FAF].”

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 19 Investigators also reviewed the possibility that the crew could The report concluded: “Correct application of both the U.S. have used one of the two INS units to identify the missed- and [ICAO] standards would result in a higher [MDA] than approach point. “The two INS selector switches were found published by the host nation … . If the flight had used this in the heading/drift-angle and cross-track distance/track-angle higher minimum altitude, it would have been above the high error selections,” the report said. “The information provided terrain [rather than] where it impacted.” by the INS displays in these selections could not have been used to determine the missed-approach point.” Investigators reviewed U.S. Air Force Instruction (AFI) 11-206 regarding the use of instrument-approach procedures. In reviewing the design of the Dubrovnik NDB approach AFI 11-206 requires that “any instrument-approach procedure, investigators found that the Republic of Croatia procedure not published in a U.S. Department of Defense Air Traffic Services Authority used the International Civil (DOD) or [U.S.] National Oceanic and Atmospheric Aviation Organization (ICAO) “Procedures for Air Administration (NOAA) flight information publication be Navigation Services — Aircraft Operations (PANS-OPS)” reviewed by the major command terminal instrument criteria for constructing instrument-approach procedures, the procedures (TERPs) specialist before it can be flown by [U.S.] report said. Air Force crews,” the report said.

The report concluded: “During review of the [NDB] approach There is an exception within the AFI that allows U.S. Air Force to Runway 12 at Dubrovnik, a number of nonstandard crews to use a non-DOD/NOAA approach chart if the weather applications of ICAO criteria were found. The host country conditions meet the minimums required to conduct a visual misapplied missed-approach criteria in the development of the flight rules (VFR) approach and landing. “The [U.S.] Air Force final-approach segment, failed to correctly identify the makes this distinction, because procedures from another source controlling obstacle and did not compute the correct [MDA]. may not meet [U.S.] Air Force criteria,” the report said. The host country did not make adjustments “Additionally, the [U.S.] Air Force cannot to the required obstacle clearance for the ensure [that] the navigational aids (e.g., excessive length of the final-approach “Correct application of [NDB] or [ILS]) supporting the procedures segment and did not make the appropriate are regularly inspected for accuracy or that height adjustment to the [MDA].” both the U.S. and obstacle data used for the procedure [are] accurate and complete.” The chart for the NDB approach to Runway [ICAO] standards would 12 at Dubrovnik depicts the KLP NDB as result in a higher [MDA] The report noted: “In a TERPs review, a the primary NAVAID on which the TERPs specialist examines the procedure approach is based and from which the final- than published by the to determine whether it meets [U.S.] Air approach course guidance is provided. Force criteria. The specialist also reviews “However, based on testimony, the host- host nation … . ” obstacle data and navigational aid nation specialist who developed the information to ensure the procedure is safe. approach intended for the pilot to receive The USAFE TERPs chief testified it takes final-approach guidance from the [CV] locator,” the report six hours or longer to complete a TERPs review.” said. Because Jeppesen published the only approach charts for The report noted: “The depiction also required a note on the Dubrovnik, the crew should not have flown the NDB depiction, ‘timing not authorized for defining the missed- approach in other-than-VFR conditions until the approach approach point,’ when timing is not authorized. The warning procedure had been reviewed by a USAFE TERPs specialist, is not indicated on the procedure; however, the Jeppesen legend the report said. clearly states that if no timing block is published, timing is not authorized.” During the investigation, investigators reviewed [a U.S.] Air Force regulation that conflicted with AFI 11-206 and Using ICAO criteria, investigators computed the MDA, first authorized the use of Jeppesen approach charts without using KLP as the primary NAVAID for the approach then using restriction and without a TERPs review. “This conflicting CV as the primary NAVAID for the approach. The MDA guidance on the use of Jeppesen approach procedures caused computed using KLP as the primary NAVAID was 860 meters confusion among the USAFE staff and 86 AW air crew (2,822 feet) and the MDA computed using CV as the primary members,” the report said. NAVAID was 790 meters (2,592 feet) (Figure 4, page 21). “Other computations provided by the [FAA using U.S. criteria] In 1995, a supplement to AFI 11-206 was issued by USAFE were slightly lower, but were well above [701 meters (2,300 that allowed non-DOD approach charts to be used without a feet)],” the report said. “No correct computation using ICAO TERPs review if the weather was better than a 1,500-foot criteria was found that duplicated the host nation–published (457-meter) ceiling and 3.1-SM (5,000-meter) visibility, the MDA.” report said.

20 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Minimum Descent Altitudes (MDAs) Based on ICAO Criteria

2,822 feet* (860 meters) KLP MDA 2,592 feet (790 meters) CV MDA Impact Point 2,175 feet (663 meters) 2,150 feet (656 meters) MDA incorrectly computed by Croatians

Cilipi Airport (Dubrovnik)

* KLP and CV MDAs correctly computed by accident investigators using International Civil Aviation Organization (ICAO) criteria. [Editorial note: KLP and CV are nondirectional radio beacons (NDBs).] Source: U.S. Air Force, International Civil Aviation Organization

Figure 4

When AFI 11-206 and the USAFE supplement were released, and are formally recorded. According to these witnesses, giving “the 86 OG commander realized the adverse impact these a ‘verbal’ waiver for an AFI does not follow any standard restrictions would have on the 86 AW’s mission,” the report agency operating practice.” said. “The 86 AW lands at many airfields where the only published approach is a Jeppesen [approach chart]; they could After the telephone conversation, “the USAFE action officer no longer land at these airfields unless the weather was 1,500 sent an e-mail to his supervisor indicating he had obtained a feet and 5,000 meters, because none of these procedures had verbal waiver from AFFSA,” the report said. As a result, a flight been reviewed by a TERPs specialist.” crew information notice (which informs flight crews of special flying requirements) was issued to all 86 OG flight crews stating The 86 OG commander sent an electronic-mail (e-mail) that a verbal waiver from AFFSA had been received, “allowing message to the USAFE director of operations “identifying air crews to fly Jeppesen approaches without complying with the difficulty in meeting this requirement and its impact on AFI 11-206 requirement for TERPs review or the USAFE the 86 AW’s mission,” the report said. “[The 86 OG Supplement 1,500-foot ceiling and [1,525-foot (5,000-meter)] commander] requested a blanket waiver to allow the 86 AW visibility weather restriction,” the report said. to fly Jeppesen approaches to the published weather minimums without TERPs review — contrary to both the In January 1996, an e-mail message was sent from U.S. Air USAFE supplement and AFI criteria.” Force headquarters (HQ Air Force) to the USAFE director of operations that disapproved the waiver to fly Jeppesen A USAFE action officer contacted the Air Force Flight approaches to published minimums without a TERPs review, Standards Agency (AFFSA) to request a waiver to AFI 11- the report said. A portion of the message stated: “AFI 11-206 206. “The action officer testified that he believed he had guidance on the use of Jeppesen products is sound,” the report obtained a verbal waiver for flying Jeppesen approaches said. “Jeppesen is essentially a ‘publishing house’ for instrument- without review from AFFSA during this conversation,” the approach procedures — they do not guarantee the safety and/or report said. “The AFFSA action officer testified that no such accuracy of their product. In fact, Jeppesen publishes a waiver was requested by or granted to USAFE. Additionally, disclaimer specifically stating they do not review or approve testimony from branch chiefs and the director of operations at the adequacy, reliability, accuracy or safety of the approach AFFSA indicated that such waivers are only provided in writing procedures they publish.”

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 21 “Proper approach development is one factor air crews ‘take rescind [the waiver to AFI 11-206] and stop using Jeppesen for granted’ every time they fly an instrument approach. When approaches until reviewed.” planning an approach, our aviators assume if they fly the procedure as depicted, they will have adequate obstacle/terrain The report concluded: “The 86 OG chief of standardization clearance. The requirements outlined in [AFI] 11-206 will help and evaluation did not ensure these actions were taken. The us maintain that high level of confidence — we should keep 17 AF standardization and evaluation officer did not later them as they are.” ensure compliance, nor did he inform 17 AF senior officials.”

As a result of this message, the USAFE director of operations Investigators discovered that there were four conflicting staff told the 86 OG commander that “86 AW air crews will directives regarding the use of Jeppesen approaches and have no authorized Jeppesen approaches to fly,” the report weather minimums (Table 1) at the time of the accident, the said. The 86 OG commander then requested that his squadron report said. AFI 11-206 required that the accident crew be able commanders “forward names of airfields that required to fly the approach and land in VFR conditions. The Dubrovnik Jeppesen approaches so they could receive a review at USAFE weather did not meet requirements for VFR operations during TERPs within the Air Operations Squadron,” the report said. the accident crew’s approach. The 86 OG commander concluded his request with the following: “My view on this: Safety is not compromised if we continue flying ops [operations] normal until approaches have Table 1 been reviewed — then we rescind [the waiver to AFI 11-206].” Comparison of Applicable Weather Minimums After receiving this message, the 86 AW commander sent the U.S. Air Force Weather Minimums Did Dubrovnik following message back to the 86 OG commander with copies Applicable for Dubrovnik Weather Meet to the squadron commanders: “[86 OG commander], come Directives NDB Runway 12 Minimums? see me ref [reference] this. … let’s step back and use common AFI 11-206, Visual conditions No sense. … these approaches have been used for years and years paragraph 8.4.2 at KLP … what do we have to do to get this ok’d? … safety first … AFI 11-206, 1,500-foot [458-meter] No thanks,” the report said. USAFE Supp 1, ceiling and 5,000-meter paragraph 8.4.2 [3.1-SM] visibility The 86 OG commander discussed the continued use of MCR 55-121, 4,800-meter Yes Jeppesen approaches during a staff meeting. “The consensus paragraph 6.74.5.1 (three-SM) visibility from the squadron commanders and [the 86 OG commander’s] 86 OG 4,800-meter Yes chief of standardization and evaluation was that safety was FCIF 95-20 (three-SM) visibility not compromised, and Jeppesen approaches could be continued NDB — Nondirectional radio beacon AFI — Air Force Instruction to be flown pending TERPs review,” the report said. “The 86 USAFE — U.S. Air Force Europe MCR — Multi-command Regulation 86 OG — 86th Operations Group KLP — Kolocep NDB AW safety officer was also present during this discussion; no FCIF — Flight Crew Information File SM — statute mile one at the staff meeting voiced any objections or raised any Source: U.S. Air Force safety concerns.”

The report noted: “The 86 OG commander then elected to fly The USAFE Supplement to AFI 11-206 required U.S. Air Force ‘ops normal’ and did not rescind [the waiver to AFI 11-206] crews to have at least a 1,500-foot ceiling and 1,525-foot [which] continued to authorize 86 AW air crews’ unrestricted visibility to fly the approach at Dubrovnik. The weather at use of Jeppesen approaches down to published weather Dubrovnik was below these minimums during the accident minimums. He understood at the time that the 86 AW was not crew’s approach. following the letter of the [AFI]. … The 86 OG commander believed that the entire chain of command knew of this action A U.S. Air Force regulation, Multi-Command Regulation and was not directing him to act otherwise.” (MCR) 55-121, and the 86 OG waiver to AFI 11-206, Flight Crew Information File (FCIF) 95-20, required the accident The report also noted that “with the extremely high operations crew to have at least [three-SM (4,800-meter)] visibility to fly tempo [of the 86 AW], the Jeppesen approach issue was pushed the approach at Dubrovnik. At the time of the accident crew’s to a lower priority and ‘dropped off [86 AW’s] radar scope.’” approach, visibility at Dubrovnik was better than three SM.

In February 1996, “a representative from 17 AF [Air Force] The report noted: “The AFI 11-206 restriction … is the only Standardization and Evaluation learned that the 86 AW was valid requirement, because it is published at the highest level still flying Jeppesen approaches to published weather ([U.S.] Air Force) and is the most restrictive provision.” minimums in violation of [previous requirements],” the report said. “[The representative] then called the 86 OG chief of The waiver to AFI 11-206 was rescinded on April 4, 1996, the standardization and evaluation and told him the 86 AW had to day after the accident. “From January–April 1996, 86 AW

22 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 missions used Jeppesen approaches without restriction, in by the European Operations Center (EOC) is limited to flight violation of AFI 11-206 and contrary to the [January 1996] following and message exchange, unless the air crew message from HQ Air Force,” the report said. specifically requests assistance,” the report said.

The investigation also revealed that the USAFE operations Investigators found that squadron supervision had intervened staff had not implemented a “cockpit/crew resource “on at least two occasions to assist air crews flying DV management (CRM) program” that was required by an AFI, missions,” the report said. On one mission, “a squadron the report said. “The 76 AS had recently developed a squadron supervisor intervened to determine the suitability of an airfield CRM program that the [accident] pilots had not yet attended. that was not listed in the European airport directory. During Tenets taught in the resource management program are another mission, a [U.S.] Congressman insisted on takeoff designed to help crews avoid mishaps like the one experienced when weather conditions were unsuitable for landing at the by IFO21 by improving skills for managing workload, air crew destination, and the squadron commander intervened on behalf decision making and enhanced situational awareness,” the of the crew, resulting in a flight delay.” report said. The investigation reviewed the possibility of external pressures Investigators reviewed the qualifications of personnel and on the accident crew to fly the mission as planned. Investigators supervision within 86 AW. “The 86 AW commander had not found that “external pressures to successfully fly the planned flown the CT-43A in his 10 months of command prior to the mission were present, but testimony revealed [that the accident accident,” the report said. “The 86 OG commander assumed crew] would have been resistant to this pressure and would command in 1995. He had flown the CT-43A once in his year not have allowed it to push them beyond what they believed of command prior to the accident. The 86 OG commander had to be safe limits,” the report said. “Specifically, the [accident] previous experience flying [Lockheed Martin] C/EC-130s. Just crew would not have begun the approach into Dubrovnik unless prior to assuming command of the 86 OG, he commanded a they thought they had the proper minimums for weather and T-1 specialized undergraduate pilot training had the required aircraft instrumentation.” squadron from 1993 to 1995.” “For the [accident] The report continued: “The 76 AS former The report added: “Both the 86 AW commander stated that both the [accident] commander and the 17 AF director of flight, it is unknown pilot and copilot had occasions within the operations testified that, in their opinion, what pressures may have last few months where they were required the 86 OG commander did not have enough to say no to a DV request. In fact, the experience to command the 86 OG.” been generated by the [accident] pilot transported the presidents of Croatia, Serbia and Bosnia-Herzegovina The 76th Airlift Squadron is part of the 86th [Department of] after the signing of the Dayton Peace Accord Airlift Wing. “The 86 AW commander, Commerce party.” and initially could not land at Sarajevo as vice commander and operations group planned. The [accident] pilot told the commander receive daily schedules and presidents they could not land.” updates for 76 AS missions; however, these agencies exercise no operational control over these sorties,” the report said. The report added: “For the [accident] flight, it is unknown what pressures may have been generated by the [Department Investigators reviewed the number of operations flown by of] Commerce party. On two previous occasions, the secretary the 76 AS. “The busiest months were February and March of commerce flew with the 76 AS. On the most recent occasion, 1996, when the air crews flew 84 sorties in a 60-day period,” April 2, 1996, the 76 AS pilot indicated there were no problems; the report said. “This usage rate can be compared to the two- this flight was completed without disruptions to the schedule. month period from October to November 1995, when only In 1993, the secretary of commerce flew with the 76 AS on a 46 sorties were flown. During the 10-day period from March C-20 [Gulfstream III] from Ramstein to Saudi Arabia. On this 27 to April 5, 1996, the CT-43A was scheduled to fly all occasion, scheduling difficulties were encountered, and a eight days, all supporting high-level distinguished visitors member of the [Department of] Commerce party attempted to (DVs), including the First Lady [wife of the U.S. President] pressure the pilots.” (DV-1), the secretary of defense (DV-2) and the secretary of commerce (DV-2),” the report said. Investigators also found that the four changes to the mission itinerary contributed to the possibility of inadequate mission The report noted: “The 76 AS commander, the former planning, the report said. commander, the operations officer and the assistant operations officer all are very experienced in DV airlift operations.” The accident crew were described as “the two best pilots in the flight,” the report said. Nevertheless, on the day of the The oversight of 76 AS missions was examined. “After the accident, “the crew demonstrated several behaviors mission is assigned to an air crew, actual supervisory oversight uncharacteristic of the normal professionalism then attributed

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 23 to these pilots, behaviors indicative of a reduced capacity to Investigators reviewed the utilization and qualification of the cope with the normal demands of the mission,” the report said. CT-43A flight mechanic program. “Former squadron supervisors indicated that the CT-43A flight mechanic program The report noted that these errors included “misplanning the in the 76 AS grew from a flying crew chief program, and was flight plan from Tuzla to Dubrovnik; flying outside the progressing into what was beginning to resemble a flight protected corridor outbound from Tuzla; excessive speed and engineer program,” the report said. “The flight manual states not having the aircraft configured by the [FAF] at KLP; and the forward crew [pilots] normally accomplish in-flight beginning the approach from KLP to Dubrovnik without formal checklists, [but] the CT-43A flight mechanics would not only approval from the tower and without a way to identify the read checklists in flight, but also change switch positions during missed-approach point.” emergency situations.”

Investigators reviewed factors that would have distracted the The report noted: “The one remaining CT-43A flight crew during the accident flight. “During the flight from Tuzla mechanic felt he was not well trained and that he relied to Dubrovnik, the crew’s misplanning of the route caused a mostly on his on-the-job training. The flight mechanic’s 15-minute delay in the planned arrival time,” the report said. formal training is based upon his duties as a maintenance “Pressure may have begun to mount for the crew to make the crew chief.” scheduled landing time, especially because responsibility for the delay now rested with the crew.” As a result of its investigation, the U.S. Air Force Accident Investigation Board concluded that the following areas did There were two additional distractions as the accident flight not substantially contribute to the accident: “Aircraft neared the FAF: “A delay in clearance to descend from 10,000 maintenance, aircraft structures and systems, crew feet and external communication with [the pilot of the aircraft qualifications, navigational aids and facilities, and medical on the ground at Dubrovnik],” the report qualifications,” the report said. “Although said. “The crew did not have the aircraft the weather at the time of the [accident] properly configured by the [FAF]. This “Instead of gaining required the air crew to fly an instrument indicated a disruption of normal crew habit approach, the weather was not a patterns, which may have further rushed additional time to slow substantially contributing factor to this other crew actions.” [accident].” down the apparent rush The report noted: “Instead of gaining of events, by entering The report concluded that the accident was additional time to slow down the apparent caused by “a failure of command, air rush of events, by entering into a holding into a holding pattern crew error and an improperly designed pattern at KLP, the crew pressed on. The instrument-approach procedure,” the report crew steadily flew approximately nine at KLP, the crew said. In reviewing the failure of command, degrees to the left of the required course. pressed on.” the report concluded that “command failed During this time, the crew could have been to comply with AFI 11-206. Commanders further distracted by trying to identify the failed to comply with governing directives missed-approach point. This would have from higher authorities. [AFI] 11-206 consumed additional attentional resources, raised the required major commands to review non-DOD approach workload and increased the likelihood of channelized procedures prior to their being flown.” attention and the resulting loss of situational awareness.” The report added: “The approach flown by the [accident] crew Investigators reviewed the passenger manifest for the accident had not been reviewed by the major command and, in flight and the process by which the manifest was established. accordance with AFI 11-206, should not have been flown.” “Interviews with members of the 76 AS indicate an extensive lack of understanding as to how the passenger manifest is The report also faulted U.S. Air Force command for failing completed and tracked,” the report said. “On the day of the “to provide adequate theater-specific training,” the report [accident], the flight plan annotation indicated the passenger said. “This was a substantially contributing factor in the manifest was located at USAFE EOC, [but] the actual passenger [accident]. Knowing operational support airlift crews in manifest for the accident aircraft was not available at the EOC.” Europe were routinely flying into airfields using non-DOD– published instrument-approach procedures, commanders did The report noted: “An actual passenger manifest could not be not provide adequate theater-specific training on these located and a passenger list had to be constructed by the U.S. instrument-approach procedures,” the report said. Embassy at Zagreb following the [accident]. This is contrary to the governing guidance in AFI 11-206, which requires the The report concluded: “Pilots with a thorough understanding filing of a passenger manifest with the flight plan or at least a of these non-DOD instrument-approach procedures would reference to where such a document can be found.” have identified the requirement to have two [ADFs] to fly the

24 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 [NDB] approach into Dubrovnik — one for final-approach The most significant error by the accident crew was their guidance and one for identifying the missed-approach point. failure “to identify the missed-approach point and execute a The CT-43A was equipped with only one ADF. Proper training missed approach,” the report said. “If the pilots had not been would have enabled the air crew to recognize they could not able to see the runway and descend for a landing, they should fly the Dubrovnik approach with the navigational equipment have executed a missed approach no later than the missed- on the aircraft. They should not have attempted to do so.” approach point. Had they executed a missed approach at the missed-approach point, the aircraft would not have impacted The report also concluded that errors committed by the flight the high terrain, which was more than one NM [1.9 kilometers] crew in planning and executing the flight combined to cause past the missed-approach point [Figure 3, page 7].” the accident. During mission planning, “although the flight crew had known for approximately 36 hours that their mission With regard to the improperly designed approach at Dubrovnik would take them into Dubrovnik, the pilots’ review of the the report said, “[The instrument-approach procedure] did not approach procedure failed to determine the approach could provide sufficient obstacle clearance in accordance with not be flown with only one ADF receiver,” the report said. internationally agreed-upon criteria,” the report said. “Additionally, the air crew improperly planned their route. This “Additionally, the [chart] depiction reflected the [KLP NDB] error added 15 minutes to their planned flight time.” as the [NAVAIDs] providing the primary approach guidance, but the approach was designed using both KLP and CV for Because of their planning error, the flight crew was late arriving approach guidance. Had the approach been properly designed, at Dubrovnik. “The pilots rushed their approach and did not the MDA would have been higher.” properly configure the aircraft prior to commencing the final segment of the approach,” the report said. “They crossed the The report noted: “The aircraft descended to the incorrectly [FAF] without clearance from the Dubrovnik tower and were designed MDA and impacted the terrain. A properly designed 80 knots [148 kilometers per hour] above final-approach MDA would have placed the aircraft well above the point of airspeed [and not] in accordance with the flight manual. They impact, even though the air crew flew nine degrees off did not enter holding at the [FAF], which was required because course.” they had not received approach clearance from the tower. Additionally, holding would have allowed them to slow and As a result of the investigation, two generals and 14 other fully configure the aircraft.” officers were disciplined. The two generals, the 86 AW commander and the 86 OG commander, were relieved of The report concluded that the crew was distracted from command in May 1996. The USAFE director of operations adequately monitoring the final-approach course because of and the 86 AW vice-commander received letters of the rushed approach, improper aircraft configuration and the reprimand.♦ call from the pilot on the ground at Dubrovnik. “They [the accident crew] flew a course that was nine degrees left of the Editorial note: This article was adapted from a report prepared correct course,” the report said. “The following possible by the U.S. Air Force Accident Investigation Board regarding reasons for the course deviation were ruled out: Equipment the crash of U.S. Air Force CT-43A, 73-1149, April 3, 1996, malfunction, performance of the navigational aids and Dubrovnik, Croatia. The 7,174-page report includes diagrams lightning or other electromagnetic effects.” and illustrations.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 25 Flight Safety Foundation CFIT Checklist Evaluate the Risk and Take Action Flight Safety Foundation (FSF) designed this controlled-flight-into-terrain (CFIT) risk-assessment safety tool as part of its international program to reduce CFIT accidents, which present the greatest risks to aircraft, crews and passengers. The FSF CFIT Checklist is likely to undergo further developments, but the Foundation believes that the checklist is sufficiently developed to warrant distribution to the worldwide aviation community.

Use the checklist to evaluate specific flight operations and to enhance pilot awareness of the CFIT risk. The checklist is divided into three parts. In each part, numerical values are assigned to a variety of factors that the pilot/operator will use to score his/her own situation and to calculate a numerical total.

In Part I: CFIT Risk Assessment, the level of CFIT risk is calculated for each flight, sector or leg. In Part II: CFIT Risk- reduction Factors, Company Culture, Flight Standards, Hazard Awareness and Training, and Aircraft Equipment are factors, which are calculated in separate sections. In Part III: Your CFIT Risk, the totals of the four sections in Part II are combined into a single value (a positive number) and compared with the total (a negative number) in Part I: CFIT Risk Assessment to determine your CFIT Risk Score. To score the checklist, use a nonpermanent marker (do not use a ballpoint pen or pencil) and erase with a soft cloth. Part I: CFIT Risk Assessment Section 1 – Destination CFIT Risk Factors Value Score Airport and Approach Control Capabilities: ATC approach radar with MSAWS ...... 0 ATC minimum radar vectoring charts ...... 0 ATC radar only...... -10 ATC radar coverage limited by terrain masking...... -15 No radar coverage available (out of service/not installed)...... -30 No ATC service ...... -30 Expected Approach: Airport located in or near mountainous terrain ...... -20 ILS ...... 0 VOR/DME ...... -15 Nonprecision approach with the approach slope from the FAF to 3 the airport TD shallower than 2 /4 degrees ...... -20 NDB ...... -30 Visual night “black-hole” approach ...... -30 Runway Lighting: Complete approach lighting system ...... 0 Limited lighting system ...... -30 Controller/Pilot Language Skills: Controllers and pilots speak different primary languages ...... -20 Controllers’ spoken English or ICAO phraseology poor ...... -20 Pilots’ spoken English poor ...... -20 Departure: No published departure procedure ...... -10 Destination CFIT Risk Factors Total (−)

CFIT Checklist (Rev. 2.2/6,000/r) Section 2 – Risk Multiplier Value Score Your Company’s Type of Operation (select only one value): Scheduled ...... 1.0 Nonscheduled...... 1.2 Corporate...... 1.3 Charter ...... 1.5 Business owner/pilot ...... 2.0 Regional ...... 2.0 Freight ...... 2.5 Domestic ...... 1.0 International ...... 3.0 Military ...... 3.0 Departure/Arrival Airport (select single highest applicable value): /New Zealand ...... 1.0 United States/Canada ...... 1.0 Western Europe ...... 1.3 Middle East ...... 1.1 Southeast Asia ...... 3.0 Euro-Asia (Eastern Europe and Commonwealth of Independent States) ...... 3.0 South America/Caribbean ...... 5.0 Africa ...... 8.0 Weather/Night Conditions (select only one value): Night — no moon ...... 2.0 IMC ...... 3.0 Night and IMC ...... 5.0 Crew (select only one value): Single-pilot flight crew ...... 1.5 Flight crew duty day at maximum and ending with a night nonprecision approach ...... 1.2 Flight crew crosses five or more time zones ...... 1.2 Third day of multiple time-zone crossings ...... 1.2 Add Multiplier Values to Calculate Risk Multiplier Total Destination CFIT Risk Factors Total × Risk Multiplier Total = CFIT Risk Factors Total (−)

Part II: CFIT Risk-reduction Factors Section 1 – Company Culture Value Score Corporate/company management: Places safety before schedule ...... 20 CEO signs off on flight operations manual ...... 20 Maintains a centralized safety function ...... 20 Fosters reporting of all CFIT incidents without threat of discipline ...... 20 Fosters communication of hazards to others ...... 15 Requires standards for IFR currency and CRM training ...... 15 Places no negative connotation on a diversion or missed approach ...... 20

115-130 points Tops in company culture 105-115 points Good, but not the best Company Culture Total (+) * 80-105 points Improvement needed Less than 80 points High CFIT risk Section 2 – Flight Standards Value Score Specific procedures are written for: Reviewing approach or departure procedures charts...... 10 Reviewing significant terrain along intended approach or departure course ...... 20 Maximizing the use of ATC radar monitoring...... 10 Ensuring pilot(s) understand that ATC is using radar or radar coverage exists ...... 20 Altitude changes ...... 10 Ensuring checklist is complete before initiation of approach ...... 10 Abbreviated checklist for missed approach ...... 10 Briefing and observing MSA circles on approach charts as part of plate review ...... 10 Checking crossing altitudes at IAF positions ...... 10 Checking crossing altitudes at FAF and glideslope centering...... 10 Independent verification by PNF of minimum altitude during stepdown DME (VOR/DME or LOC/DME) approach ...... 20 Requiring approach/departure procedure charts with terrain in color, shaded contour formats ...... 20 Radio-altitude setting and light-aural (below MDA) for backup on approach ...... 10 Independent charts for both pilots, with adequate lighting and holders ...... 10 Use of 500-foot altitude call and other enhanced procedures for NPA...... 10 Ensuring a sterile (free from distraction) cockpit, especially during IMC/night approach or departure ...... 10 Crew rest, duty times and other considerations especially for multiple-time-zone operation ...... 20 Periodic third-party or independent audit of procedures ...... 10 Route and familiarization checks for new pilots Domestic ...... 10 International ...... 20 Airport familiarization aids, such as audiovisual aids...... 10 First officer to fly night or IMC approaches and the captain to monitor the approach...... 20 Jump-seat pilot (or engineer or mechanic) to help monitor terrain clearance and the approach in IMC or night conditions ...... 20 Insisting that you fly the way that you train ...... 25

300-335 points Tops in CFIT flight standards 270-300 points Good, but not the best Flight Standards Total (+) * 200-270 points Improvement needed Less than 200 High CFIT risk Section 3 – Hazard Awareness and Training Value Score Your company reviews training with the training department or training contractor ...... 10 Your company’s pilots are reviewed annually about the following: Flight standards operating procedures ...... 20 Reasons for and examples of how the procedures can detect a CFIT “trap” ...... 30 Recent and past CFIT incidents/accidents ...... 50 Audiovisual aids to illustrate CFIT traps ...... 50 Minimum altitude definitions for MORA, MOCA, MSA, MEA, etc...... 15 You have a trained flight safety officer who rides the jump seat occasionally ...... 25 You have flight safety periodicals that describe and analyze CFIT incidents...... 10 You have an incident/exceedance review and reporting program...... 20 Your organization investigates every instance in which minimum terrain clearance has been compromised ...... 20 You annually practice recoveries from terrain with GPWS in the simulator...... 40 You train the way that you fly ...... 25

285-315 points Tops in CFIT training 250-285 points Good, but not the best Hazard Awareness and Training Total (+) * 190-250 points Improvement needed Less than 190 High CFIT risk Section 4 – Aircraft Equipment Value Score Aircraft includes: Radio altimeter with cockpit display of full 2,500-foot range — captain only ...... 20 Radio altimeter with cockpit display of full 2,500-foot range — copilot ...... 10 First-generation GPWS...... 20 Second-generation GPWS or better ...... 30 GPWS with all approved modifications, data tables and service bulletins to reduce false warnings ...... 10 Navigation display and FMS ...... 10 Limited number of automated altitude callouts ...... 10 Radio-altitude automated callouts for nonprecision approach (not heard on ILS approach) and procedure...... 10 Preselected radio altitudes to provide automated callouts that would not be heard during normal nonprecision approach...... 10 Barometric altitudes and radio altitudes to give automated “decision” or “minimums” callouts ...... 10 An automated excessive “bank angle” callout ...... 10 Auto flight/vertical speed mode ...... -10 Auto flight/vertical speed mode with no GPWS ...... -20 GPS or other long-range navigation equipment to supplement NDB-only approach ...... 15 Terrain-navigation display ...... 20 Ground-mapping radar...... 10

175-195 points Excellent equipment to minimize CFIT risk 155-175 points Good, but not the best Aircraft Equipment Total (+) * 115-155 points Improvement needed Less than 115 High CFIT risk

Company Culture + Flight Standards + Hazard Awareness and Training + Aircraft Equipment = CFIT Risk-reduction Factors Total (+) * If any section in Part II scores less than “Good,” a thorough review is warranted of that aspect of the company’s operation. Part III: Your CFIT Risk

Part I CFIT Risk Factors Total (−) + Part II CFIT Risk-reduction Factors Total (+) = CFIT Risk Score (±) A negative CFIT Risk Score indicates a significant threat; review the sections in Part II and determine what changes and improvements can be made to reduce CFIT risk.

In the interest of aviation safety, this checklist may be reprinted in whole or in part, but credit must be given to Flight Safety Foundation. To request more information or to offer comments about the FSF CFIT Checklist, contact Robert H. Vandel, director of technical projects, Flight Safety Foundation, 601 Madison Street, Suite 300, Alexandria, VA 22314 U.S., Phone: 703-739-6700 • Fax: 703-739-6708. Aviation Statistics

Worldwide Commercial Jet Transport Accident Rates Declined in 1995

There were nine fatal accidents in 1995 compared with 14 in 1994, and the fatal-accident rate was lower than in all but two years since 1960.

FSF Staff Report

Worldwide commercial jet transport accident rates were lower The accident rate for U.S.–registered aircraft was 2.40 per in 1995 than in 1994, according to data released by McDonnell million departures, compared with 3.34 per million departures Douglas Corp. for non-U.S.–registered aircraft.

The 1995 accident rate declined to 2.90 per million departures, The approach and landing phases of flight, in combination, from 2.97 per million departures in 1994 (Figure 1, page 31). accounted for more accidents than any other phase — 20 — The fatal-accident rate also fell, from 0.88 per million compared with 31 in 1994 (Figure 3, page 33). Eleven takeoff departures in 1994 to 0.46 per million departures in 1995 accidents were an increase from the 1994 total of five. (Figure 2, page 32). That rate was lower than in all but two years of the since 1960; only 1984 (0.2) and 1986 (0.35) had Four 1995 accidents were classified as controlled-flight-into- lower fatal-accident rates. terrain (CFIT) accidents. They involved a McDonnell Douglas DC-9, a Boeing 757, a Boeing 737 and a McDonnell Douglas The data are compiled in Commercial Jet Transport: Aircraft MD-80. Accident Statistics 1995. Among the other data in the 1995 McDonnell Douglas accident summary were the following: The data excluded accidents in which neither the aircraft’s equipment, nor its crew, nor flight operational procedures • The total number of accidents in 1995 was 44, compared were factors. Those excluded accidents were tabulated with 43 in 1994; separately, however, and they included six pushback accidents (in four of which an aircraft collided with a tug), • There were nine fatal accidents in 1995, compared with three ground collisions, one accident in which a passenger 14 in 1994; was injured during an evacuation and 15 turbulence accidents. Five turbulence accidents injured flight attendants, eight • Hull-loss accidents numbered 20 in both 1994 and 1995; injured passengers and two injured both flight attendants and and, passengers.

• Weather was a contributing factor in 15 (34 percent) of The statistics included only commercial jet transports accidents and 11 (55 percent) of hull-loss accidents in 1995. manufactured in the United States or in western Europe.♦

30 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 FLIGHT SAFETY FOUNDATION •

Worldwide Commercial Jet Transport Accident Rates, 1960–1995

60 FLIGHTJULY–AUGUST SAFETY • DIGEST 1996 50

40

30

20 Accidents per Million Departures 10

0 1960 1965 1970 1975 1980 1985 1990 1995 Year Source: McDonnell Douglas Corp.

Figure 1 31 2FLIGHTSAFETY FOUNDATION • 32

Worldwide Commercial Jet Transport Fatal-accident Rates, 1960–1995

16

14

12

10

8

6

4 FLIGHT SAFETY DIGEST JULY–AUGUST • 1996 Fatal Accidents per Million Departures Fatal Accidents per Million 2

0 1960 1965 1970 1975 1980 1985 1990 1995 Year

Source: McDonnell Douglas Corp.

Figure 2 FLIGHT SAFETY FOUNDATION •

Worldwide Commercial Jet Transport Accidents, by Phase of Operation, 1958–1995 Number of Accidents

FLIGHTJULY–AUGUST SAFETY • DIGEST 1996 by Phase, 1991Ð1995 91 92 93 94 95 Phase

26 29 39 26 16 Landing 586 7 12 7 5 4 Approach 271 10 14 6 5 11 Takeoff 265 47433 Climb 104 75441 Cruise 82 35803 Taxi 80 20113 Descent 47 12042 Go-around 26 00100 Ground Event 16 An accident may involve more than one phase of operation; therefore the sum of the items may 02000 Engine Start 4 be more than the total accidents shown. 01100 Parked 2 0 100 200 300 400 500 600 Number of Accidents

Source: McDonnell Douglas Corp.

Figure 3 33 Publications Received at FSF Jerry Lederer Aviation Safety Library

FAA Advisory Circular Outlines New Method for Designing Airport Pavement for Boeing 777

Book offers a new look at procedures for avoiding midair collisions.

Editorial Staff

Advisory Circulars (ACs) Aviation Administration (FAA) Advisory Circular (AC) 21- 5M. Jan. 19, 1996. 1 p. Available through GPO.* Guidelines for Operational Approval of Windshear Training Programs. U.S. Federal Aviation Administration (FAA) This AC announces the availability of the 1995 revised version Advisory Circular (AC) 120-50A. Feb. 9, 1996. 10 pp. of the Summary of Supplemental Type Certificates. The summary Appendices. Available through GPO.* lists supplemental type certificates (STCs) issued by the FAA, addressing design changes to aircraft, engines or propellers, for This AC provides guidance for the approval of low-altitude which STC holders have claimed design rights or intention to wind-shear training for operations under U.S. Federal Aviation distribute. The summary is available on computer disk. The AC Regulations (FARs) Parts 121 and 135. The U.S. National contains price and ordering information. Transportation Safety Board (NTSB) has determined that low- altitude wind shear has been a prime cause of aircraft accidents. Dynamic Evaluation of Seat Restraint Systems and In 1985, the FAA contracted with a consortium of aviation Occupant Protection on Transport Airplanes. U.S. Federal specialists, including Flight Safety Foundation; the training Aviation Administration (FAA) Advisory Circular (AC) aid developed by that consortium focused on the causes and 25.562-1A. Jan. 19, 1996. 46 pp. Appendices. Available effects of wind shear and developed ways for pilots to identify, through GPO.* avoid and recover from wind-shear encounters. The information provided in the wind-shear training aid enables This AC provides information and guidance about the dynamic aircraft operators to create or update their own wind-shear testing of seats used in transport category aircraft in compliance training programs. Sections of this AC describe the approval with U.S. Federal Aviation Regulations (FARs) Part 25. The process and the objectives of acceptable wind-shear ground background and intent of aircraft seat testing are discussed; training programs and flight simulator training. equipment and test facilities are described.

This AC cancels AC 120-50, Guidelines for Operational This AC supersedes AC 25.562-1, Dynamic Evaluation of Seat Approval of Windshear Training Programs, dated Oct. 10, Restraint Systems and Occupant Protection on Transport 1989. Airplanes, dated March 6, 1990.

Announcement of Availability: Summary of Supplemental Obstruction Marking and Lighting. U.S. Federal Aviation Type Certificates — August 1995 Edition. U.S. Federal Administration (FAA) Advisory Circular (AC) 70/7460-1J.

34 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Jan. 1, 1996. 58 pp. Appendices, figures, index. Available Automated Weather Observing Systems (AWOS) for Non- through GPO.* Federal Applications. U.S. Federal Aviation Administration (FAA) Advisory Circular (AC) 150/5220-16B. Nov. 11, 1995. This AC describes FAA standards for marking and lighting 53 pp. Figures. Available through GPO.* structures that may obstruct aircraft in flight. Any temporary or permanent object exceeding a height of 61 meters (200 feet) An automated weather observing system (AWOS) is a above ground level or exceeding obstruction standards in U.S. computerized system that measures one or more weather Federal Aviation Regulations (FARs) Part 77, Subpart C, must parameters, prepares weather observations and broadcasts these be marked and/or lighted under normal circumstances. observations to pilots via very high frequency (VHF) radio or navigational aids (NAVAIDs). This AC contains the FAA Chapters in this AC describe the colors and patterns of paint standard for nonfederal AWOS. It provides guidance regarding for marking structures, configurations and standards for red program elements that should be incorporated into an AWOS. and white lights, marking of catenary support structures and marking of moored balloons and kites. Appendix 1 contains Principal changes in this AC from the previous version, AC illustrated specifications for painting and lighting various types 150/5220-16A, Automated Weather Observing Systems of structures, such as radio towers, chimneys, water towers (AWOS) for Non-Federal Applications, dated June 12, 1990, and bridges. include the following: The FAA states its commitment to adopting a version of the International Aviation Routine Aviation Inspector Work Site Access. U.S. Federal Aviation Weather Format (METAR); AWOS maintenance technicians Administration (FAA) Advisory Circular (AC) 13-1. Dec. 28, must comply with the qualification requirements in the most 1995. 2 pp. Available through GPO.* recent version of FAA Order 6700.20A, Non-Federal Navigational Aids and Air Traffic Control Facilities; VHF and To facilitate safety inspection, FAA aviation safety ultra high frequency (UHF) radio parameters must be included inspectors (ASIs) and air carrier cabin safety specialists in the maintenance manual; and AWOS manufacturers are (ACCSSs) need unhindered and uninterrupted access to encouraged to design systems in accordance with FAA aircraft, airports, aviation facilities and accident sites. This Standards 019 and 020 and the U.S. National Electric Code. AC briefly describes the duties of ASIs and ACCSSs and provides information on how to obtain the necessary Aircraft Weight and Balance Control. U.S. Federal Aviation identification cards (FAA Form 8000-39) and credentials Administration (FAA) Advisory Circular (AC) 120-27C. Nov. (FAA Form 110A) to gain access to secure and restricted 7, 1995. 14 pp. Appendix. Available through GPO.* airport areas to conduct duties. A sample FA Form 8000-39 is included in the AC. This AC provides guidance for certificate holders who are required to obtain approval of a weight-and-balance control Airspace Utilization Considerations in the Proposed program under U.S. Federal Aviation Regulations (FARs) Part Construction, Alteration, Activation and Deactivation of 121. It will also be useful to FARs Part 135 operators who are Airports. U.S. Federal Aviation Administration (FAA) affected by proposed requirements in the Commuter Operations Advisory Circular (AC) 70-2C. Nov. 29, 1995. 6 pp. Appendix. and General Certification and Operations Requirements Notice Available through GPO.* of Proposed Rulemaking (60 FR 16230, March 29, 1995).

The purpose of this AC is to advise persons who propose to Aircraft operators may submit any program that indicates that construct, activate or deactivate civil or joint-use (civil/ their aircraft will be properly loaded and will not exceed, during military) airports. The AC also outlines some airspace usage flight, approved weight-and-balance limitations. Approval is factors to be considered at the beginning of the planning stage based on evaluation of the program presented for the particular when constructing or altering an airport. aircraft and the operator’s ability to implement the proposed program. The FAA requires prior notification of new construction or of a change in the status of an existing airport to ensure conformity This AC addresses the following subjects pertaining to weight- to plans and policies for the allocation of airspace. The FAA, and-balance control systems: Methods for establishing, after receiving notification, will consider the effects the monitoring and adjusting an individual aircraft or fleet; loading proposed airport would have on navigable airspace. This AC schedules; procedures for using loading schedules; load describes the types of projects that require notification, projects manifests; procedures for personnel involved in aircraft loading that do not require notification and how to submit a notice of and operation; and operational performance factors. This AC airport construction or alteration plans. cancels AC 120-27B, Aircraft Weight and Balance Control, dated Oct. 25, 1990. This AC cancels AC 70-2D, Airspace Utilization Considerations in the Proposed Construction, Alteration, Airport Pavement Design for the Boeing 777 Airplane. U.S. Activation and Deactivation of Airports, dated Aug. 1, 1979. Federal Aviation Administration (FAA) Advisory Circular

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 35 (AC) 150/5320-16. Oct. 22, 1995. 50 pp. Available through 2 through 14 explain how to read surface-analysis charts, radar GPO.* summaries, severe weather–outlook charts and winds-and- temperatures–aloft charts. These sections also explain how to This AC provides FAA-recommended thickness design standards interpret radar reports and satellite pictures. The final section for pavements serving the Boeing 777. The unique tri-tandem provides tables and conversion graphs that can be used to arrangement (three pairs of wheels in a row) on the main landing decode weather messages during preflight and in-flight gear of the B-777 produces an unprecedented airport planning, and in transmitting pilot reports. pavement-loading configuration. A new method of design, based on layered-elastic analysis, has been developed to calculate the pavement thickness required to support the aircraft. Reports

The new method, which is computer-based and operates under Performance of a Continuous Flow Passenger Oxygen Mask Microsoft Windows,® is code named LEDFAA (Layered at an Altitude of 40,000 Feet. Garner, Robert P. U.S. Federal Elastic Design — Federal Aviation Administration), version Aviation Administration (FAA) Office of Aviation Medicine. 1.2. This AC discusses standards and guidelines for flexible Report no. DOT/FAA/AM-96/4. February 1996. 13 pp. pavements, rigid pavements and overlay pavements. Appendix Figures, references. Available through NTIS.** 1 provides a list of related reading materials. Appendix 2 contains the user manual for the LEDFAA pavement-design Keywords: program. 1. Oxygen Mask 2. Aircraft Passengers Specification for Obstruction Lighting Equipment. U.S. 3. Hypoxia Federal Aviation Administration (FAA) Advisory Circular (AC) 150/5345-43E. Oct. 19, 1995. 15 pp. Tables. Available This study evaluates the ability of a redesigned continuous- through GPO.* flow oxygen mask to deliver an adequate oxygen supply to aircraft passengers. Four test subjects breathed pure oxygen The specifications contained in this AC are recommended by for two hours through a pressure-demand mask immediately the FAA in all applications involving obstruction-lighting before high-altitude exposure; on exposure to a simulated equipment, and are mandatory for airport projects receiving altitude of 35,000 feet (10,675 meters), the subjects switched federal funds under the airport grant assistance program. Only to the continuous-flow mask. After heart and respiratory rates equipment that is qualified in accordance with these and blood-oxygen saturation levels were stabilized, the specifications will be listed in AC 150/5345-53, Airport simulated altitude was increased to 40,000 feet (12,200 meters). Lighting Equipment Certification Program. The subjects were then restored to ground-level air pressure in increments of 5,000 feet (1,525 meters); their blood-oxygen This document supersedes AC 150/5345-43D, dated July 15, saturation levels were monitored at each successive point of 1988. Principal changes include the elimination of the distinction simulated descent. The study notes that blood-oxygen between Class 1 and Class 2 for the steady-burning red saturation levels did not approach baseline levels for hypoxic obstruction light (L-810), the inclusion of a classification for exposure at any time during the test. This study concludes the flashing red obstruction light (L-885) and the inclusion of that the mask design appears to offer protection from hypoxia requirements for dual lighting systems. Chromaticity standards resulting from high-altitude exposure. for aviation colors have also been altered to conform to those of the International Civil Aviation Organization (ICAO). Crashes of Instructional Flight: Analysis of Cases and Remedial Approaches. Baker, Susan P.; Lamb, Margaret W.; Aviation Weather Services. U.S. Federal Aviation Li, Guohua; Dodd, Robert S. U.S. Federal Aviation Administration (FAA) Advisory Circular (AC) 00-45D. 1995. Administration (FAA) Office of Aviation Medicine. Report 77 pp. Tables, figures. Available through GPO.* no. DOT/FAA/AM-96/3. February 1996. Tables, references. 44 pp. Available through NTIS.** This AC, which updates the 1985 Aviation Weather Services (AC 00-45C), explains how to use and interpret coded weather Keywords: reports, forecasts and weather charts. The AC’s 15 sections 1. Flight Training contain information needed by pilots, including charts and 2. Instructional Flights tables that can be applied directly to flight planning and in- 3. Aircraft Crashes flight decision making. 4. NTSB Accident Database 5. ASRS Incident Database Section 1 describes the Aviation Weather Service Program, a joint service of the U.S. National Weather Service, the FAA More than 300 accidents each year involve instructional flights; and the U.S. Department of Defense. This section lists the instructional flights also account for one-third of all midair services that each agency provides to civilian aviation. Sections collisions. This report describes research conducted by the FAA

36 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Civil Aeromedical Institute (CAMI) to identify the experimental situation that completely excluded FPSs. Without circumstances surrounding instructional flight accidents. strips, controllers took significantly longer to grant requests and spent significantly more time looking at the plan view For this study, U.S. National Transportation Safety Board display. Controllers also compensated for the lack of strips by (NTSB) accident records for instructional accidents involving requesting more flight plan readouts. The report notes that fixed-wing civilian aircraft between 1989 and 1992 were controller performance and perceived workload did not differ examined. In addition, the U.S. National Aeronautics and Space between the two simulated conditions. Administration (NASA) Aviation Safety Reporting System (ASRS) was searched for incident reports relating to [For a more detailed account of this report, see Airport instructional flights during 1992 and 1993. Operations Volume 22 (May–June 1996).]

The analysis revealed that 1,226 instructional aircraft were Airport Privatization: Issues Related to the Sale or Lease of involved in accidents during the years in question, resulting in U.S. Commercial Airports. Statement of Gerald L. Dillingham, 250 deaths and 128 serious injuries. Thirty-eight instructional Associate Director, Transportation Issues Resources, aircraft were involved in midair collisions. Other major causes Community, and Economic Development Division, U.S. of accidents included loss of control on landing, crosswinds General Accounting Office (GAO), before the Subcommittee and failure to recover following stalls. Student pilots on solo on Aviation, Committee on Transportation and Infrastructure, flights were involved in 51 percent of all accidents examined, U.S. House of Representatives, Feb. 29, 1996. Report no. but instructors were present in half of all accidents following GAO/T-RCED-96-82. 14 pp. Available through GAO.*** stalls and one-third of accidents caused by fuel starvation. Keywords: This report concludes that instructors contribute to accidents 1. U.S. Airports — Privatization both directly, during dual instruction, and indirectly, by failing 2. U.S. Airports — Management to monitor their students. It says that greater emphasis must be placed on avoiding stalls and midair collisions during flight Gerald L. Dillingham testified before the U.S. House of training. The fundamental principles of takeoff and landing Representatives Subcommittee on Aviation about the potential flight dynamics must be understood before solo touch-and-go influence of privatization on commercial airports in the United practice. The report suggests that the importance of these States. Dillingham’s statement addressed the current extent of factors be communicated to flight instructors during their initial private-sector participation in commercial airports, training as well as during preparation for relicensing. impediments to more extensive privatization and the implications of further privatization on airline passengers, How Controllers Compensate for the Lack of Flight Progress airlines, the U.S. government and other stakeholders. Strips. Albright, Chris A.; Truitt, Todd R.; Barile, Ami B.; Vortac, O. U.; Manning, Carol A. U.S. Federal Aviation Dillingham testified that, while commercial airports in the Administration (FAA) Office of Aviation Medicine. Report United States are almost exclusively owned by municipalities no. DOT/FAA/AM-96/5. February 1996. 14 pp. Figures, tables, or states, the private sector has a significant role in their references, appendices. Available through NTIS.** operation. Private companies — e.g., airlines, concessionaires, construction contractors — provide most airport services. More Keywords: extensive privatization is inhibited by economic and legal 1. Air Traffic Controllers restrictions: The U.S. Federal Aviation Administration (FAA) 2. Automation permits some privatization in the form of contracts for airport 3. Cognitive Psychology management and leases for the use of terminals by private 4. Flight Progress Strips companies, but there is concern that the sale or lease of an 5. Flight Progress Data entire airport would violate the municipal owner’s obligations as a federal grantee. Current law requires that public-airport Future increases in air traffic are expected to place even greater revenues must be used to pay capital and operating costs and demands on the U.S.’s already overburdened and air traffic cannot be diverted for nonairport purposes. control (ATC) system. Flight progress strips (FPSs), which display important flight data to the air traffic controller, have Dillingham also stated that it would be difficult to predict how been considered to be indispensable in separating air traffic. stakeholders might be affected by extensive airport As part of the FAA program to update the system, the continued privatization. For example, possible cost increases to airlines use of FPSs is under debate. and passengers would depend on whether airport charges to airlines continued to be regulated. Likewise, effects on the This report examines the viability of a “stripless” environment. federal budget would depend on whether privatized airports Twenty air traffic controllers from the FAA Atlanta Air Route would have access to tax-exempt federal loans and whether Traffic Control Center volunteered to participate in a dynamic extensive privatization would contribute to an overall reduction simulation comparing standard ATC operations with an in the funding of federal grants.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 37 Dillingham’s testimony also included a brief history of U.S. Coordinating Agency for Supplier Evaluation (CASE). The airport privatization and described the growing popularity of computer-based System for Training Aviation Regulations airport privatization in other countries. (STAR) is examined in Chapter 3. Chapter 4 describes the Human Factors Information System (HFIS), a hypertext, Index to FAA Office of Aviation Medicine Reports: 1961 multimedia documentation software system, and Chapter 5 through 1995. Collins, William E.; Wayda, Michael E. U.S. assesses the information needs of the aviation maintenance Federal Aviation Administration (FAA) Office of Aviation community on the Internet. Medicine. Report no. DOT/FAA/AM-96/1. January 1996. 79 pp. Available through NTIS.** Chapter 6 analyzes a human factors program to prevent on- the-job injuries that was initiated by Northwest Airlines. A Keywords: human factors audit program for maintenance tasks is 1. Aviation Medicine examined in Chapter 7 and the reliability of checklists is 2. Research Reports discussed in Chapter 8. Chapters 9 and 10 address aircraft 3. Office of Aviation Medicine inspection issues. Chapter 11 presents a study of teamwork in maintenance, and Chapter 12 reports on proposed changes to This index provides a cumulative list of research reports U.S. Federal Aviation Regulations (FARs) Part 65 concerning released by the FAA Civil Aeromedical Institute (CAMI) certification requirements for aviation maintenance between 1961 and 1995. The index is divided into three technicians. Each chapter is followed by its own appendices. sections: reports listed in chronological order, reports listed alphabetically by author and reports grouped by subject This report concludes with a selection of papers presented at headings. The reports listed in this index are also available the 1994 FAA meeting on Human Factors in Aircraft through NTIS.** Maintenance and Inspection. These include “Human Factors in Aviation Maintenance,” by U.S. Federal Air Surgeon Jon Human Factors in Aviation Maintenance — Phase Five L. Jordan, and “Overview of FAA ND Research at Sandia Progress Report. Shepherd, William T. A special report Labs,” by Patrick Walter, Ph.D. prepared for the U.S. Federal Aviation Administration (FAA) Office of Aviation Medicine. Report no. DOT/FAA/AM-96/ Civil Tiltrotor Development Advisory Committee Report to 2. January 1996. 274 pp. Figures, tables, appendices. Available Congress in Accordance with PL 102-581. U.S. Department through NTIS.** of Transportation (DOT), Research and Special Programs Administration. December 1995. Two volumes. 344 pp. Keywords: 1. Human Factors Guide The U.S. Congress directed the U.S. Secretary of 2. Aviation Maintenance Transportation to establish a Civil Tiltrotor Development 3. Computer-based Job Aids Advisory Committee under Section 135 of the Airport and 4. Computer-based Instruction Airway Safety, Capacity, Noise Improvement, and Intermodal 5. Digital Documentation Transportation Act of 1992 (PL 102-581). The committee’s 6. Ergonomics Audits purpose was to examine the costs, technical feasibility and 7. Team Training economic viability of developing civil tiltrotor (CTR) aircraft 8. On-line Electronic Information and to assess the potential for integrating CTR aircraft into 9. Visual Inspection the national transportation system. This report presents the 10. NDI Performance findings of the committee: CTR is technically feasible and 11. Training and Certification can be developed by U.S. industry, but successful CTR introduction depends on additional research and Since 1989, the FAA Office of Aviation Medicine (OAM) has development, as well as infrastructure planning before conducted research on human factors in aviation maintenance. production can begin; CTR infrastructure development Its research program involves universities, government should be integrated into national and local transportation laboratories and private industries, and encompasses fields systems plans; a CTR system could become economically from basic scientific experimentation to applied studies in viable without government subsidization; and CTR could also airline work environments. Each year since the beginning of reduce airport congestion. the program, the OAM has reported on the primary research conducted during that year; this document reports on the fifth The committee recommends that a partnership between public year (Phase Five) of the program. and private interests be formed to address CTR institutional, infrastructure and coordination issues with the U.S. government. Chapter 1 provides an overview of the year’s projects. Chapter The committee also recommends that the CTR aircraft and 2 describes two applications in mobile computing software infrastructure research, development and demonstration for aviation inspectors, the government-based Performance program continue; this program will cost approximately US$600 Enhancement System (PENS) and the industry-based million during the next 10 years, with government and industry

38 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 sharing the cost. The DOT is charged to initiate a multimodal means of preventing ruptures to the containment bag is to use study of options to increase intercity transport capacity. an oversized bag from which as much residual air as possible has been evacuated. This report concludes that polyethylene Volume I of this report summarizes the findings and bags, properly used, can be an effective alternative to rigid recommendations of the Civil Tiltrotor Development Advisory secondary-containment receptacles. In addition, the use of Committee and its responses to questions submitted by polyethylene bags for the transport of biological specimens Congress. Volume II provides a supplement covering the CTR could reduce shipping costs dramatically if future regulations technical issues discussed. require all such specimens to be treated as infectious substances. An Economical Alternative for the Secondary Container Used for Transporting Infectious Disease Substances. An Experimental Abdominal Pressure Measurement Device Mandella, Joseph, G. Jr.; Garner, Robert P. A special report for Child ATDs. DeWeese, Richard L. A special report prepared prepared for the U.S. Federal Aviation Administration (FAA) for the U.S. Federal Aviation Administration (FAA) Office of Office of Aviation Medicine. Report no. DOT/FAA/AM-95/ Aviation Medicine. Report no. DOT/FAA/AM-95/30. 29. December 1995. 5 pp. Figures, tables. Available through December 1995. 8 pp. Figures, tables, references. Available NTIS.** through NTIS.**

Keywords: Keywords: 1. Medical Specimens 1. Abdominal Pressure 2. Infectious Substances 2. Child Restraints 3. Anthropometry 3. Airplane Passenger Seats 4. Transport 5. IATA This report describes an experimental instrumentation system 6. ICAO developed at the U.S. Federal Aviation Administration (FAA) Civil Aeromedical Institute (CAMI) Biodynamics Research The exposure of biological specimen containers to high Section that measures abdominal pressure in child altitudes during air transport may cause ruptures and leakage. anthropomorphic test dummies (ATDs). This system was Safe containment is therefore a matter of great concern, developed as part of a project to evaluate child restraint devices especially when infectious specimens are shipped via air. in airplane seats. The abdominal pressure measurement system Current guidelines provided by the International Civil was installed in a two-year-old child ATD and in a six-month- Aviation Organization (ICAO) and recognized by the U.S. old child ATD; both ATDs were subjected to dynamic impact Department of Transportation (DOT) require a double sled tests to assess the efficacy of various child restraint container for the packaging of infectious substances: A devices. The restraint devices evaluated were booster seats, primary receptacle with a leakproof seal is placed within a standard lap belts and an adult lap-held device called the “belly rigid, leakproof secondary container with a layer of absorbent belt.” material separating the two. Because of concern about the transmission of AIDS (acquired immunodeficiency The report concludes that the experimental pressure system syndrome), the DOT is considering amending existing provided a quantitative method of measuring the restraint loads regulations to require all biological specimens to be packaged imposed on the abdominal sections of child ATDs. The report as if they were infectious. Such an amendment could lead to also notes that the experimental system recorded a “spike” in a significant increase in packaging and shipping costs. abdominal pressure during the tests of all three restraint devices (the two-year-old child ATD wearing a standard lap belt This study tested the durability of adhesive-closure received the lowest abdominal pressure load), and discourages polyethylene bags when exposed to high altitudes. The the use of any child restraint device that places extreme polyethylene bags contained specimens packaged in ICAO- pressure on the abdominal region. recommended primary containers. Testing consisted of two phases: 1) Identifying the most effective combination of [For a detailed account of child restraint–device testing at bag composition, thickness and size; and 2) determining CAMI, see Cabin Crew Safety Volume 29/30 (November– the most appropriate packing techniques for bags used in December 1994/January–February 1995).] air transport. Some Effects of 8- vs. 10-Hour Work Schedules on Test Both phases used a hypobaric chamber to expose the test bags Performance/Alertness of Air Traffic Control Specialists. to a simulated altitude of 45,000 feet (13,725 meters). The Schroeder, David J.; Rosa, Roger R.; Witt, L. Alan. A special results of the first phase of testing indicated that differences report prepared for the U.S. Federal Aviation Administration in the composition and thickness of the bags did not (FAA) Office of Aviation Medicine. Report no. DOT/FAA/ significantly alter their ability to withstand the pressure AM-95/32. December 1995. 17 pp. Figures, tables, references. differential. The second phase indicated that the most effective Available through NTIS.**

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 39 Keywords: The Kidde hidden-fire test consisted of a set of small fires in 1. Shift Work sites that simulated the conditions of a hidden fire (for example, 2. Fatigue behind the walls or beneath the floor of the cabin). Four Halon 3. Human Performance 1211 hand-held extinguishers were first tested to determine 4. Air Traffic Control their effectiveness; results varied from 45 percent to 60 percent 5. Sleep extinguishment, depending on the quantity of Halon contained in the extinguisher and the discharge rate. This report reveals the results of a study that compared the 10-hour, four-day rotating shift schedule with the traditional Limited testing was conducted on six Halon replacements: FM- eight-hour, 2-2-1 rapidly rotating schedule. For this study, 26 200, FE-25, CEA-410, CEA-614, FE-36 and Triodide. The air traffic control specialist volunteers worked the 10-hour, results of this testing appear to be similar to those for the Halon four-day schedule for one week; 26 worked the eight-hour, 1211 extinguishers. This study concludes that the Kidde 2-2-1 schedule. hidden-fire test is suitable for evaluating the comparative performance of hand-held extinguishers and may therefore be The U.S. National Institute of Occupational Health and Safety used to define a minimum performance standard for (NIOSH) Fatigue Test Battery, which was developed to extinguishers containing Halon replacement agents. The quantify changes in cognitive skills, perceptual motor appendices provide all data resulting from the test study. performance and reported subjective feelings associated with shift work, was administered to each group three times during Aviation Safety in Alaska. U.S. National Transportation Safety each work day: at the beginning of each day, two hours before Board (NTSB) Safety Study no. NTSB/SS-95/03. November the end of the work day and at the close of the day. Additional 1995. 117 pp. Figures, appendices. Available through NTIS.** data on sleep patterns, mood and physical complaints were also gathered. The NTSB studied Alaska’s aviation environment to identify deficiencies in aviation safety procedures. To obtain The study concluded that the test performances of air traffic information, the NTSB reviewed its own investigations of control personnel who worked the 10-hour shift did not differ accidents that occurred in Alaska between 1983 and mid-1995; significantly from those who worked the eight-hour schedule commercial pilots were also surveyed, and Alaskan during the first four days of the work week. Nevertheless, test infrastructure personnel were interviewed. performances of air traffic controllers working the eight-hour, 2-2-1 schedule suffered a notable decline during the night shift Their findings revealed that fatal accident rates for Alaskan of the fifth day. Diminished alertness was also noted for some commuter airlines have decreased in recent years, but still subjects across the days of the work week under both schedules. remain higher than the rates for commuter airlines in the rest Significantly, changes in test performance and in subject mood of the United States. Six contributory factors are examined: corresponded with a decrease in reported sleep time throughout 1) The pressures on pilots and commercial operators to provide the test week. reliable air service in an environment and with an infrastructure that are often incompatible with these demands; 2) the [For details of another experiment on controller shift-work adequacy of weather observation; 3) the adequacy of airport schedules, see Airport Operations Volume 21 (May–June inspection; 4) the effects of current regulations for pilot flight, 1995).] duty and rest time on safety; 5) the adequacy of the present instrument flight rules system and the enhancements required The Development of a Hidden Fire Test for Aircraft Hand to reduce Alaskan commuter airlines and air taxi operators’ Extinguisher Applications. Chattaway, A. U.K. Civil Aviation dependence on visual flight rules; and 6) the needs of special Authority (CAA) Paper No. 95013. December 1995. 76 pp. aviation operations in Alaska. Figures, tables, appendices. Available through U.K. CAA.**** This study concludes with practical recommendations to the In accordance with the Montreal Protocol on substances that U.S. Federal Aviation Administration (FAA), the U.S. Postal deplete the ozone layer, production of Halon fire suppressants Service (USPS), the U.S. National Weather Service (NWS) ceased on Jan. 1, 1994. U.S. Federal Aviation Regulations and the State of Alaska for managing safety risks in the (FARs)/Joint Aviation Regulations (JARs) 25.851 currently Alaskan aviation environment. Recommendations include the requires a Halon 1211 or equivalent hand-held extinguisher to implementation of a model program to demonstrate a low- be installed on transport category aircraft; a replacement agent altitude instrument flight rules system by the end of 1997; will have to be found that duplicates Halon 1211’s ability to the development of limited consecutive-day duty periods for extinguish hidden fires on aircraft. The U.K. Civil Aviation flight crews; the improvement of weather-observation Authority (CAA) invited competitive bids from research technologies and systems; the establishment of training organizations in the United Kingdom to develop a hidden-fire programs to enable “mike-in-hand” reports of airport test to evaluate possible Halon 1211 replacement agents. Kidde conditions; and the establishment of a more flexible International Research was awarded the contract in March 1995. performance standard for postal delivery. The NTSB calls

40 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 for a joint effort among the above-named agencies to 3. World War II, 1939–1945 accomplish these goals. 4. Aircraft Industry — Military Aspects

Appendix A contains the NTSB survey questions submitted Building the B-29 presents the social and industrial history of to U.S. Federal Aviation Regulations (FARs) Part 135 pilots the construction of the most important and most expensive and operations personnel working in Alaska. Appendix B weapon produced by the United States during World War II. compares statistical data on accidents, flight hours and accident The B-29 Superfortress bomber was designed to fly long-range rates from 1986 to 1994 in Alaska with those of the rest of the missions over strategic targets. This book traces its United States. development from the first proposals in the late 1930s for a “flying fortress” that was heavier, more easily handled and able to carry a bigger bomb load than the B-17, to the testing Books and modifications of the prototype XB-29 in 1940, to coordination between the U.S. government and aircraft manufacturers such as The Boeing Co., Bell Aircraft and the Handbook of Pilot Selection. Hunter, David R.; Burke, Eugene Glenn L. Martin Co. to begin production in 1941. The grand- F. Brookfield, Vermont, U.S.: Ashgate Publishing Co., 1995. scale project initiated for the rapid mass production of the B- 213 pp. Figures, tables, references, appendices, index. 29 played a crucial part in revitalizing the U.S. economy during the war. This book describes the methods for selecting aircraft pilots. It provides a comprehensive review of the research on pilot Occupational Health in Aviation: Maintenance and Support selection and discusses the scientific methodology underlying Personnel. Ribak, Joseph; Rayman, Russell B.; Froom, Paul the development of effective selection processes. The book (editors). San Diego, California, U.S.: Academic Press, 1995. will interest professional psychologists looking for information 238 pp. Figures, tables, references, index. on the current status of research in pilot selection; it will also interest aviation managers seeking a foundation for a well- Keywords: designed pilot-selection system. 1. Aviation Ground Crews 2. Health and Hygiene Chapter titles follow the chronological sequence of a selection system: “Planning for Selection,” “Deciding What to Although much has been published on occupational health with Measure,” “Deciding How to Measure,” “Evaluating the respect to flight crews, information on the health hazards that Selection System” and “Putting It All Together.” Topics include threaten maintenance and ground support crews is scarce. In criteria used in the selection process, methods to obtain this book, chapter authors describe these hazards and also information for assessment of applicants and the reliability of recommend preventive and remedial measures. The intended test results. Professional and legal standards are briefly audience for this book is occupational health personnel discussed, as is the question of whether personality assessments affiliated with general, civil or military aviation. are valid indicators of performance abilities. Diverse health and safety concerns are analyzed. In “Clinical The history of pilot-selection research is presented, going back Toxicology,” Paul Froom describes the toxic effects on the to its beginnings in World War I recruit-testing programs. human body of various chemical substances encountered by Research in this field, however, remains almost entirely aviation ground-support crews (e.g., benzene, cadmium, focused on the military: The authors’ own review of pilot- cyanide, lead and mercury). Talma Kushnir examines “Stress selection literature reveals that only seven of 254 studies in Ground Support Personnel,” major sources of which include conducted focused on pilots in nonmilitary settings. The final shift work, having responsibility for other people’s lives, time chapter, “Future Directions,” examines changes in the job pressures, monotonous work and poor working conditions. requirements for pilots and in the psychological assessment Asher Pardo conducts a “Walk-through Survey” to identify of applicants. Appendix A provides tables of pilot-selection health and safety hazards in the workplace. studies. Appendix B offers a hypothetical example that leads the reader step-by-step through the selection process. An Russell B. Rayman’s “The Electromagnetic Spectrum and extensive bibliography is also provided. Chemical Hazards” describes some of the toxic chemicals found in aircraft maintenance operations. Joseph Ribak Building the B-29. Vander Meulin, Jacob. Washington, D.C., discusses dangerous sanitary conditions and preventive U.S.: Smithsonian Institution Press, 1995. 104 pp. hygiene in the chapter titled “Biological Hazards.” Other Photographs, figures, references. chapters discuss common work-related health problems, such as lower-back pain and contact dermatitis, ground accidents Keywords: and ergonomic risk factors for ground personnel. In the final 1. B-29 Bomber — Design and Construction chapter, Ralph Shain describes the components of an aviation 2. United States — History occupational health program.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 41 Avoiding Mid-Air Collisions. Krause, Shari Stamford. Tab delayed one hour and 45 minutes because airport closure was Books Practical Flying Series. New York, New York, U.S.: necessitated by a snowfall, the B-737 took off from Runway McGraw-Hill, 1995. 222 pp. Figures, appendix, index. 36. It was unable to climb and struck the 14th Street Bridge that crossed the . The airplane then plunged Keywords: into the river. Seventy passengers, four crew members and 1. Airplanes — Collision Avoidance four persons in vehicles on the bridge were killed.]

Safety Recommendation A93-127-132, issued recently by the Each case study is followed by “Practical Applications and U.S. National Transportation Safety Board (NTSB), urges the Lessons Learned,” which take the reader through a point-by- U.S. Federal Aviation Administration (FAA) to assume a more point analysis of the factors that led to the accident. active role in instructing flight personnel on factors that can lead to midair collisions. This book examines some of those The chapter titled, “Pilot Judgment and Decision Making,” factors in depth. The practical information and applications contends that good judgment can be developed by learning to provided reflect the issues emphasized in the Safety avoid certain hazardous attitudes. Krause describes these Recommendation. attitudes as anti-authority — “The regulations are for someone else”; impulsiveness — “I must act now”; invulnerability — Avoiding Mid-Air Collisions begins with Krause’s own account “It won’t happen to me”; machismo — “I’ll show you. I can of a near-miss incident in her student-pilot days. Learning from do it”; and resignation —“What’s the use?” To aid students in her experience that “all it takes is one mistake” for even an identifying hazardous attitudes, this chapter contains a series experienced pilot to become involved in a midair collision, of hypothetical situations and describes possible attitudes the author explains how to avoid colliding with other aircraft toward them. in flight. The book is arranged in a textbook format, with bold- face section headings and subheadings addressing successively Discussion questions conclude each chapter, and the appendix detailed subjects within each general topic. contains additional review questions.♦

The first chapter, “Mid-Air Collision Avoidance: Myths and Realities,” examines the “see-and-avoid” concept as well as Sources the limitations of human vision, blind spots and optical illusions. Side-by-side and front-to-side scanning methods are * Superintendent of Documents discussed in this chapter. “The Role of Air Traffic Control U.S. Government Printing Office (GPO) [ATC]” explores ATC’s relationship with the pilot. The lessons Washington, DC 20402 U.S. of Chapter 1 are re-examined in light of real aviation examples in “Mid-Air Collisions: Flying by the Myth, Dying by the ** National Technical Information Service (NTIS) Reality.” “Crew Resource Management [CRM]: It’s Not Just 5285 Port Royal Road for the Big Boys,” discusses how general-aviation pilots can Springfield, Virginia 22161 U.S. apply CRM techniques used by airlines to their own flight (703) 487-4600 procedures. *** U.S. General Accounting Office (GAO) Other chapters address “Distraction: Confusion and Chaos in P.O. Box 6015 the Cockpit,” “The World of Stress Management,” “Traffic- Gaithersburg, MD 20884-6015 U.S. Alert and Collision-Avoidance Systems” and “Trends and Telephone: (202) 512-6000; Fax: (301) 258-4066 Issues” in collision avoidance. Case studies, many of which are well-known aviation disasters, emphasize crucial points ****U.K. Civil Aviation Authority (CAA) throughout the book. For example, in the chapter on CRM the Printing and Publications Services 1982 accident is examined. [, Greville House a Boeing 737-222, originated at National Airport, Washington, 37 Gratton Road D.C., U.S. After the flight’s scheduled departure time was Cheltenham GL50 2BN

42 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Updated U.S. Federal Aviation Administration (FAA) Regulations and Reference Materials

Advisory Circulars (ACs)

AC No. Date Title

39-7C 11/16/95 Airworthiness Directives (Cancels AC 39-7B, Airworthiness Directives, dated 4/8/78).

150/5320-6D 1/30/96 Airport Pavement Design and Evaluation (Change 1 to 150/5320-6D, Airport Pavement Design and Evaluation, dated 7/7/95).

23.1521-2 4/24/96 Type Certification of Oxygenates and Oxygenated Gasoline Fuels in Part 23 Airplanes with Reciprocating Engines (Change 1 to AC23.1521-2, Type Certification of Oxygenates and Oxygenated Gasoline Fuels in Part 23 Air- planes with Reciprocating Engines, dated 1/23/93).

90-91A 5/13/96 National Route Program (Cancels AC90-91, National Route Program, dated 4/24/92).

U.S. Federal Aviation Regulations (FARs)

Part Date Subject

Part 23 12/28/95 Airworthiness Standards: Normal, Utility, Acrobatic, and Commuter Category Airplanes (incorporates Amendment 23-47, “Revision of Authority Citations,” adopted 12/8/95; Amendment 23-48, “Airworthiness Standards: Airframe Rules Based on European Joint Aviation Requirements,” adopted 3/11/96; Amend- ment 23-49, “Airworthiness Standards: System and Equipment Rules Based on European Joint Aviation Requirements,” adopted 3/11/96; Amendment 23- 50, “Airworthiness Standards: Flight Rules Based on European Joint Aviation Requirements,” adopted 3/11/96; and Amendment 23-51, Airworthiness Stan- dards: Powerplant Rules Based on European Joint Aviation Requirements,” adopted 3/11/96).

Part 121 12/28/95, Certification and Operations: Domestic, Flag, and Supplemental Air 1/19/96, Carriers and Commercial Operators of Large Aircraft (incorporates Amend- 2/26/96, ment 121-250, “Air Carrier and Commercial Operator Training Programs,” 3/19/96 adopted 12/8/95; Amendment 121-251, “Commuter Operations and General Certification and Operations Requirements,” adopted 12/12/95; Amendment 121-252, “Revision of Authority Citations,” adopted 12/20/95; and Amend- ment 121-253, “Operating Requirements: Domestic, Flag, Supplemental, Com- muter, and On-Demand Operations: Editorial and Terminology Changes,” adopted 1/17/96).

Part 33 8/19/96 Airworthiness Standards: Aircraft Engines (incorporates Amendment 33-18, “Airworthiness Standards: Aircraft Engines, New One-Engine-Inoperative (OEI) Ratings, Definitions and Type Certification Standards,” adopted 5/30/96).

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 43 Accident/Incident Briefs

MD-87 Crew Makes Mistaken Approach To Military Airport

Sightseeing helicopter downed by fuel exhaustion at air show.

Editorial Staff

The following information provides an awareness of problems centerline. The closest point between the two aircraft during through which such occurrences may be prevented in the fu- the approach was 61 meters (200 feet) vertically and 110 meters ture. Accident/incident briefs are based on preliminary infor- (360 feet) horizontally. Investigators determined that traffic mation from government agencies, aviation organizations, alerts were issued to both pilots by the tower, as required, and press information and other sources. This information may that both pilots initially reported each other in sight and not be entirely accurate. maintaining visual separation.

‘Wrong’ Field in Sight

McDonnell Douglas MD-87. No damage. No injuries.

The aircraft with two flight crew members and 10 other crew members on board was on a positioning flight from London’s to , South Wales. Weather at Cardiff was reported as 3,500 feet (1,068 meters) scattered Unexpected Company on Final and visibility 10 miles (16 kilometers).

Boeing 757. Cessna 182RG. No damage. No injuries. While on approach to Cardiff, the crew were instructed by approach control to maintain 5,000 feet (1,525 meters) and The Boeing 757 was on final straight-in approach to Runway expect an instrument landing system (ILS) approach to 28R at a U.S. airport. The Cessna 182 was making an approach Runway 12. After a further cleared descent to 4,000 feet to Runway 28L. (1,220 meters), the flight crew informed the controller that they had the airport in sight and asked for a visual approach, The tower had called out the traffic and the Boeing 757 captain, which was not approved because of inbound visual flight the pilot flying, observed the Cessna on base leg for Runway rules (VFR) traffic. The flight was cleared to descend to 2,500 28L at the same altitude. The Boeing captain said that as the feet (763 meters) and told to expect a “short radar-to-visual Cessna turned final, it appeared that it was going to overshoot approach.” and fly directly over the B-757. Anticipating a potential problem, the B-757 captain began a descent as the aircraft’s A few moments later, the controller advised that a nearby traffic-alert and collision avoidance system (TCAS) “descend” military airport was active and told the MD-87 crew to turn to warning activated. The Cessna was then observed in a left a heading of 220 degrees. The flight was then instructed to bank, correcting for the overshoot. descend to 1,700 feet (519 meters), to continue the left turn to a heading of 150 degrees and report the airport in sight. The An investigation determined that the tower controllers did not crew replied that they still had the field in sight. The Cardiff observe course deviations by either aircraft even though radar controller admonished the crew, “Don’t fly south of the final indicated that the Cessna was north of the Runway 28L approach due to ... [military airport] activity.”

44 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 Two minutes later, the flight was cleared to land on Runway The captain immediately returned to the departure airport, 12. A few seconds later, the controller transmitted: “Confirm and the landing was uneventful. An inspection of the cargo that you are not approaching [the military airport], you seem hold determined that the drive motors of a wheelchair in the to be west of [the military airport] at the moment.” The hold had become activated, causing them to overheat and controller then added: “Break off and reposition onto Runway create an acrid odor. Investigators determined that the 12 at Cardiff ... .” At the time of the incorrect approach, an wheelchair had been loaded without its motors being locked aircraft at the military airport was preparing to take off from in the off position. Runway 08 southwest-bound.

The MD-87 captain said that he was not aware that there was another airport in the vicinity of Cardiff, and that he realized he was lining up on the wrong runway beginning with the turn on final. The European airline’s company approach charts used by the flight crew did not show the military airport in the vicinity of Cardiff. New approach charts showing the nearby military airport have been issued along with a warning notice about the military airport’s proximity to Cardiff. Ice Causes Fatal Stall

Rockwell Turbo Commander 690. Aircraft destroyed. Two fatalities.

The twin-turbo prop aircraft was descending through 5,400 feet (1,647 meters) mean sea level when the pilot reported to air traffic control that he was clear of clouds and that he had accumulated some rime ice.

One minute later, ATC heard the passenger say, “We’ve got Instrument Failure Follows big problems.” Radar contact was then lost. An investigation Static Discharges determined that the aircraft had stalled after encountering ice while on final approach. The pilot and the passenger were killed British Aerospace ATP. Minor damage. No injuries. in the twilight accident.

The ATP twin-engine turbo-prop was descending from 11,000 feet (3,355 meters) when multiple static discharges occurred on both the captain’s and the first officer’s windshields; both electronic flight instrument system (EFIS) displays failed.

The flight was continued on primary flight displays, but a right- engine fire-warning indication was received a few minutes later. The aircraft landed without incident, and the three crew members and 13 passengers were not injured. An investigation determined that 24 static-discharge wicks were defective and Missed Approach Ends in Forest that several of the wicks were not bonded to the airframe. The failure of the engine-fire warning systems was traced to a Cessna Citation II. Substantial damage. Two fatalities. contaminated electrical connector. The Citation twin-engine jet was on a night approach in instrument meteorological conditions to a European airport. Smoking Wheelchair Motor Prompts During the approach, the pilot canceled his instrument flight Return to Departure Airport rules (IFR) flight plan.

De Havilland DHC-8. No damage. No injuries. After canceling IFR, the pilot initiated a missed approach. The aircraft crashed into a forest, 30 degrees nose down and in a The twin-turboprop Dash 8 was climbing shortly after takeoff 60-degree left bank. The two flight crew members were killed. from a Canadian airport when the cabin attendant reported a An investigation determined that the aircraft had stalled during strong odor in the passenger cabin. the go-around.

FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 45 Fire fighters arrived at the accident scene and reported no fuel leakage in the wreckage. Accident investigators also determined that the helicopter’s fuel system was intact and that there was no evidence of tank or fuel-line rupture. Investigators found only residual fuel in the tank.

The pilot and one passenger were seriously injured in the accident, and a second passenger was killed. The helicopter was destroyed. Weather at the time of the accident was reported as visual meteorological conditions with clear skies and Two Killed When Helicopter visibility 20 miles (32 kilometers). Strikes Tower Power Lines Snare Hughes 369D. Aircraft destroyed. Two fatalities. Local Low-level Flight

The helicopter was engaged in construction work on a Hughes 369HS. Substantial damage. Three serious injuries. transmission tower when it impacted the tower and then struck the ground. The helicopter was on a sightseeing flight along a river when it struck power lines. The pilot reported that he had flown along The pilot and a construction worker on the tower were killed. the river several times that day at a higher altitude. The helicopter was destroyed. Weather at the time of the accident was reported as visual meteorological conditions and An investigation determined that the power lines were about 15-knot (28 kilometer-per-hour) winds. nine meters to 15 meters (30 feet to 50 feet) above ground level. The pilot and two passengers were seriously injured. Weather at the time of the accident was reported as visual Helicopter Damaged by Arrow Strike meteorological conditions with 5,000 feet (1,525 meters) broken and visibility 20 miles (32 kilometers). Bell 206L. Substantial damage. No injuries.

The Bell 206 was on a local observation flight when its tail Pilot Loses Control After Flying into Fog rotor was struck by an arrow. The pilot was able to land the aircraft without incident, and neither he nor the two passengers Enstrom F-28C. Aircraft destroyed. One injury. on board were injured. The helicopter was being ferried to a new location at night An investigation determined that the tail rotor had been when the non-instrument-rated pilot lost control of the aircraft substantially damaged by the arrow strike. The individual after it flew into a fog bank. suspected of firing the arrow was arrested. Weather at the time of the incident was reported as visual meteorological conditions Weather at the time of the accident was reported as instrument with 4,400 feet (1,342 meters) overcast and visibility 10 miles meteorological conditions with 400 feet (122 meters) overcast (16 kilometers). and visibility two miles. The pilot told accident investigators that he was in cruise flight at 800 feet (244 meters) above ground level, following a highway, when he flew into the fog. Fuel Exhaustion Shortens Sightseeing Flight The pilot immediately slowed the aircraft and began a 180- degree climbing right turn. During the turn, the pilot lost control Enstrom F-28C. Aircraft destroyed. One fatality and two of the helicopter, and it began to descend in a dive. The pilot serious injuries. then saw lights on the highway and increased collective pitch, but the main rotor blades contacted trees. The helicopter veered The helicopter was conducting short sightseeing rides as part of to the right across the highway where it struck more trees, air-show activities when it lost power and struck the ground. collided with the ground and rolled on its side. The commercial Witnesses reported seeing the aircraft descending backwards in pilot received minor injuries and a private-pilot passenger was a tail-low attitude until it struck the ground. not injured.♦

46 FLIGHT SAFETY FOUNDATION • FLIGHT SAFETY DIGEST • JULY–AUGUST 1996 BLANK INSIDE BACK COVER Best Practices and Processes for Safety Hyatt Regency Dubai Dubai, United Arab Emirates November 11–14, 1996 A Joint Meeting of

Flight Safety Foundation International Federation International 49th annual of Airworthiness Air Transport International Air Safety Seminar 26th International Conference Association

For more information contact Flight Safety Foundation Telephone: (703) 739-6700 Fax: (703) 739-6708

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